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Eclipse not able to resolve Maven dependency

I have been working on a Java Maven project and my way of using it in Eclipse was to build it on command line and then import in Eclipse. The problem that I was facing is even though the project built successfully, eclipse was not able to resolve dependencies correctly.
This problem would usually go by cleaning, Maven updating and deleting and importing. However, this time it did not get resolved by following these steps. I tried a lot of already existing answers but nothing worked for me. However, I observed that the classpath is not getting created correctly:
I'm seeing that one of the dependency jars is marked as missing
I tried to create the Eclipse .classpath file using:
mvn eclipse:clean
mvn eclipse:eclipse
But mvn eclipse:eclipse fails with the following message:
Failed to execute goal on project consultation: Could not resolve
dependencies for project
company.compliance:consultation:jar:1.0-SNAPSHOT: Failure to find
company.compliance:commons:jar:1.0-SNAPSHOT in
http://maven.ia55.net/company was cached in the local repository,
resolution will not be reattempted until the update interval of
company-mvn-repository has elapsed or updates are forced -> [Help 1]
I read in some of the answers that this can also happen if m2e is not configured properly (it should be pointing to the commandline maven and not embedded maven). When I checked I saw that I don't even have m2e so in installed it. I don't know how to configure it to point to my Maven.
However, I doubt that this problem is because of the plugin not working otherwise I would not have been able to work in Eclipse peacefully till now.
So my other question is, isn't the success of mvn clean package enough to warrant that eclipse should not have any compilation errors regarding dependencies or does scope of dependency also plays a role and that I should work on getting the jar in the repo.
Is there any other possible issue that I am missing?

The issue got resolved. Earlier i was only importing the project that i wanted to work on. After importing all the projects in the directory which contained the pom, eclipse resolved the dependencies. Have no clue how this worked but it did.

Why is m2e not finding some of my snapshot dependencies from nexus?

In eclipse when I build I get the following warnings:
2/18/14, 4:30:35 PM MST: [INFO] Using org.maven.ide.eclipse.wtp.WarLifecycleMapping lifecycle mapping for MavenProject: com.foo:bar:14.4.19-SNAPSHOT # C:\dev\code\apps\iv\pom.xml.
2/18/14, 4:30:35 PM MST: [WARN] The POM for com.foo.libraries:s2j:jar:1.0.3-SNAPSHOT is missing, no dependency information available
2/18/14, 4:30:35 PM MST: [WARN] The POM for com.foo.libraries:caching:jar:1.0.1-SNAPSHOT is missing, no dependency information available
2/18/14, 4:30:35 PM MST: [WARN] The POM for com.foo.libraries:email:jar:1.0.1-SNAPSHOT is missing, no dependency information available
...
And so on. The build does not complete and I am unable to get anything more in my target directory than the m2e-wtp/web-resources folder.
When I build from the command line, there are no issues, these artifacts are found just fine. They certainly are in my local repository, why does this happen?
Some further details from experiments:
Deleting my local repository and rebuilding in eclipse downloaded some of the artifacts, but resulted in more artifacts to not be found (originally I had 5 missing artifacts, now I have 7). Those that were not found were not downloaded from Nexus.
After having deleted the repository in the experiment above, I then built from the command line and those artifacts that had been listed as missing were downloaded and the build was successful. However, going back to eclipse results in the same errors (despite now having them in my local repository).
Inside eclipse when I "Run As" > "Maven Install" The missing artifacts are downloaded and are found. If I do an eclipse "Build Project" after this I still get the same issue.
Other projects within eclipse are experiencing the same issues on the same artifacts.

Something similar happened to me once. I've checkout com.foo:bar as well as com.foo.libraries:s2j, but I haven't configure the library as maven project in eclipse. So the maven install worked just fine (only the pom file was used), but the eclipse build failed.
So check that all the projects are configured as maven ones and try Maven > Update project and check Force update of snapshots and Clean projects.

I found the solution.
Apparently when I did a mass close of workspace resolved projects some of them were left in a bad state. It looks like eclipse was trying to find the jar as a workspace resolved project, but the projects were closed and caused the result that they didn't exists (instead of looking at my local repository).
Once I opened (and then closed) the respective project for each of the missing dependencies they were then found in my local repository.

IntelliJ IDEA creates wrong maven snapshot dependencies

Why it could be that IDEA is creating maven snapshot dependencies with a path like: (the first time only for 4 out of ~10 dependencies)
C:\Users\<user>\.m2\repository\com\foo\bar\some\1.6.0-SNAPSHOT\some-1.6.0-20130708-101124-145.jar
I fixed them by hand in the .ipr file just to see, what will happen. I wrote:
C:\Users\<user>\.m2\repository\com\foo\bar\some\1.6.0-SNAPSHOT\some-1.6.0-SNAPSHOT.jar
and after opening IDEA, the references in java code worked fine, but under Maven Projects the dependencies were marked red. After clicking on Reimport All Maven Projects the wrong dependencies came back - now not only the 4, but almost all snapshots I am referencing.
I have looked in the pom.xml files, the version in the dependencies is always 1.6.0-SNAPSHOT.

File/Settings.../Maven/Allways update snapshots
This did it for me + hope that can help (even me in the future).

Build your project using maven
mvn clean install
now all the dependencies downloaded to your local Maven repository.(you can define it.)
Then all the dependencies are in one location. Go to module(project) properties in IntelliJ IDEA by right click on that project. set your local repository as maven repository. Then re import dependencies. Now you solved that issue. If you have more issues leave a comment here

In Eclipse m2e, how to reference workspace project?

How can I reference another workspace project using Eclipse m2e?
Do I have to add a project dependency in the project setting? But in that case the dependency is not shown in the pom.
If I set them in the pom, it will not reference the project in workspace but reference the jar in the local repository. Quite annoying, anyone can help?

The correct way to do this is the following:
Use the dependencies section in the POM file exclusively, don't fiddle with the Eclipse project references. Right-click the project, then select Maven > Update Project Configuration to reset the project to the Maven default settings. This way, m2e has ownership of the dependencies.
Make sure all referenced projects are open in Eclipse and have the Maven nature enabled.
Check the Maven settings for each project, make sure that groupId, artifactId and version match with the projects you have open in Eclipse. So if the project you depend on has version 1.0.0-SNAPSHOT in Eclipse, make sure that the depending project's POM file references version 1.0.0-SNAPSHOT in the dependencies section.
Enable Workspace Resolution for each of the projects. Right-click the project, then Maven > Enable Workspace Resolution.
Finally, if the projects are still not resolved, right-click the project again, then Maven > Update Project
This should solve your problem. If after this, your dependencies are still referenced from the file system, check the groupId, artifactId and especially version of each dependency again.
Also check if you don't have any errors in your project - try to run Maven install.

I'd go even further than this.
If you've ever run mvn eclipse:eclipse on your project then you're probably in trouble. I had a situation where I had both a "Referenced Libraries" section and a "Maven Dependencies" section in my eclipse project, with conflicting library versions, causing eclipse and myself inevitable confusion.
The safest thing I found was to run mvn eclipse:clean from the command line then go back in to eclipse, refresh the project, "OK" the resulting problem dialog, and then go Maven > Update Project. This sorted it all out for me.

When eclipse is messed up with importing and deleting several projects, you may need to rebuild index of maven repositories. Here is a way that I have done.
Check if an referenced project is recognized as a maven project by eclipse properly.
In menu bar, click Window -> Show View -> Other...
When 'Show View' window pops up, select Maven -> Maven Repositories
In Maven Repositories window, You should see your project as jar file in Local Repositories -> Workspace Projects
If you can not find your project in Workspace Projects, right click on Workspace Projects and select Rebuild Index.
Update maven of an referencing project
Right click on the referencing project, Maven -> Update Project... -> OK

You also need to make sure that you are running the correct goals.
If you don't run the install goal then it won't be copied to your repository and won't compile.
To learn more about goals have a look at https://maven.apache.org/guides/introduction/introduction-to-the-lifecycle.html

With kudos to #nwinkler's response, the main problem is matching the version number.
A common scenario is that if you are developing a set of projects that are version lock-steped with each other - for example, a project and a set of library projects that are not very loosely coupled, such that a library API might change in a version to be consumed by the relevant app project version, but may change in a way that is incompatible with a past or future version of the app project.
The correct way to set Maven dependencies in such a configuration (and it is also the recommended practice) is to have the app consume specific versions of the libraries - so, for example, if you rebuild an old version of the app, it will use the library version that it previously compiled with.
With the app project's POM library dependency set to a release version (lets say 1.0.0), and while working on the next release with both the app and library projects set to a SNAPSHOT release (lets say 2.0.0-SNAPSHOT), the m2e will not resolve the library version correctly, and will likely download an old version, so that trying to use Eclipse features like "Open Decleration" will target the download jar (sometimes without even a source attachment) which can be pretty annoying.
One way to work around that is to set the app POM dependency version to a range, so instead of depending on 1.0.0, you'd depend on [1.0.0-). With an open range like that, m2e will happily find your workspace library project. But you'd want to set it back to the "correct" version before committing, building and publishing - and this can be very error prone.
My solution is to use build profiles and set a custom profile for m2e, like this:
Set your dependency version with a property, to the version you want to publish against:
...
<properties>
<my.library.version>1.0.0</my.library.version>
</properties>
<dependencies>
<dependency>
<groupId>my.group</groupId>
<artifactId>my.library</artifactId>
<version>${my.library.version}</version>
</dependency>
</dependencies>
...
Then add a profile section with an active by default profile that does nothing, and an Eclipse-specific profile that overrides the library version property with a range:
...
<profiles>
<profile>
<id>default</id>
<activation><activeByDefault></activeByDefault></activation>
</profile>
<profile>
<id>eclipse</id>
<properties>
<my.library.version>[1,)</my.library.version>
</properties>
</profile>
</profiles>
...
Finally go to your project properties, and under "Maven" type "eclipse" into "Active Maven Profiles":
Then "Apply and close".
Eclipse m2e will then always see the version range and will resolve dependencies from the eclipse project (even if you have the library installed in the local Maven repo, as the Eclipse project will have a higher version number), but other builders will see the original, strict, version number.

Error opening Maven POM file dependency hierarchy in Eclipse - "Project read error"

When I open a POM file and click on the "Dependency Hierarchy" tab at the bottom, it gives me the error, "Project read error". It works with other projects in the same workspace, just not with this one. Any ideas?
EDIT
In response to #Yhn's answer.
Running the compile and package phases outside of Eclipse from the command-line work as expected. It compiles the application and builds the final WAR file.
Eclipse is indeed pointing to the default location of the Maven settings.xml file, so it should be aware of the custom repositories that are defined in it (my company has its own Maven repository).
I can open and edit the POM file from Eclipse, so it must have read/write permissions to the file.
The project is not configured in Eclipse as a Maven project, so I cannot run the package phase from Eclipse (I can only run it from the command-line).
I wonder if it has anything to do with the fact that I was having trouble building the project with Maven 3 because apparently some of the transitive dependencies are configured for Maven 1, which Maven 3 does not support (this is my theory anyway, based on some of the error messages). I can build the project with Maven 2, but I still get messages such as the following:
Downloading: http://dist.codehaus.org/mule/dependencies/maven2/org/codehaus/xfie/bcprov-jdk14/133/bcprov-jdk14-133.pom
[INFO] Unable to find resource 'org.codehaus.xfire:bcprov-jdk14:pom:133' in repsitory mule (http://dist.codehaus.org/mule/dependencies/maven2)
It must be able to find these dependences however, because it downloaded the JARs just fine and can build the application. It seems like the problem is that the dependencies don't have POM files associated with them, which is maybe why they cannot be used with Maven 3. This might also be why I cannot view the Dependency Hierarchy in Eclipse.
EDIT 2
I converted the project to a Maven project by going to "Configure > Convert to Maven Project". When I open the POM file, I see the error:
ArtifactDescriptorException: Failed to read artifact descriptor for woodstox:wst (Click for 140 more)
(woodstox:wst is another transitive dependency of the project). An error appears in the "Markers" view for seemingly every depedency and transitive dependency in my project. However, I can successfully build the project by doing a "Run As > Maven build". (Edit: This might be because this project has no Java source code, but the JARs of the dependencies correctly appear in the final WAR.) The Dependency Hierarchy still gives the same error--"Project read error".
About the "Unable to find resource" messages--but this only appears for a handful of transitive dependencies. The project has many more transitive dependencies, but these messages do not appear for them. It seems like, because the dependencies do not have POM files, that Maven tries to search for them every time the project is built. Is this normal not to have POMs??
How might I go about getting a repo manager? Is this something that would have to be installed on the company's Maven repository or can you install it on your own workstation?

I had this problem with some non-maven jars that I needed to include in my maven project. I put the jars in my local repository using this maven command:
mvn install:install-file -Dfile=/test/gov.nist.xccdf-1.2.jar -DgroupId=gov.nist -DartifactId=xccdf -Dpackaging=jar -Dversion=1.2
Then I referred to them as dependencies in my pom.xml:
<dependency>
<groupId>gov.nist</groupId>
<artifactId>xccdf</artifactId>
<version>1.2</version>
<type>jar</type>
<scope>compile</scope>
</dependency>
This worked fine for a while, but I must have upgraded something in eclipse, and I started getting the error you describe.
The fix is to take them out of the local repository, and redo the install-file asking maven to generate a pom for you:
mvn -DgeneratePom=true install:install-file -Dfile=/test/gov.nist.xccdf-1.2.jar -DgroupId=gov.nist -DartifactId=xccdf -Dpackaging=jar -Dversion=1.2
The command will cause a pom to be generated in the same directory (within your local repo) where the jar is placed.
In recent versions of eclipse maven support, the maven build is still done with maven 2 (if you right-click your pom.xml, choose run as mvn package for example). The dependency analysis is now done with an embedded maven 3 plugin, which doesn't like a dependency that has no pom.xml.

I had the same problem. If you made your project a maven project, you should run:
Right Mouse Click on project | Maven | Update Dependencies or
Right Mouse Click on project | Maven | Update Project Configuration
That worked for me.

Given the information through the comments:
mvn compile/mvn package work through console (I'm assuming outside of eclipse). Based on that, the POM file should be correct and dependencies can be resolved.
However; it could be that eclipse's settings aren't correct. For example, if eclipse has some own maven properties (instead of the default ~/.m2/settings.xml file); I can imagine it to fail resolving dependencies configured in the settings.xml used by maven itself. The settings for this should be in the Eclipse Preferences # Maven > User Settings.
Also make sure that Eclipse can actually read the file (not locked, correct rights, etc).
Should this seem to be correct; can you try to run the mvn goal compile from eclipse? You can do this by right-clicking the project and selecting run as > maven package. That way it should run maven with the same settings as eclipse is using, and might show any additional errors in it's configuration.
--
In response to additional information:
Basically it tells you - when using Maven 2 - that it can't find a dependency resource (in this case bcprov-jdk14) in the given repository (codehaus/mule). When I search that maven module (bcprov-jdk14) I find it in the Maven central repo (through our local nexus) # repo1.maven.org/maven2. Maybe that causes the error you're getting with Maven2?
And as the Maven 3 doc says; for Maven 1.x repo's; you should proxy them through a repo manager that can serve it to you as a maven 2 repository (I believe we do that here too for some repo's through Sonatype Nexus OSS)
ps.: Enabling maven dependency management in eclipse should be enough to be able to use maven run targets; if you would want to test it.
--
Sound like it can be multiple problems... given that the normal maven build works fine, one would think that maven can at least get the artifacts it depends upon and their dependencies... Yet, eclipse doesn't seem to be able to.
Double check if your Eclipse internet connection settings are correct? Since you were talking about a company repo, I'm assuming there will probably also be a proxy (I had to set up my Eclipse to use that one too; though for plugins (see next point)).
Another possibility, from experience, can be a rule-based proxy block on *.pom url requests (our proxy here blocks that to force usage of the local repo manager, how evil and annoying that is :(). You might want to try and open the .pom file it tries to download manually in your browser to see if this is the case (I can't, for example...).
To get the repo set up, you would probably have to ask the one responsible for the repository to add it as a maven2 proxy.
At the very least, it seems Eclipse is having issues getting the dependency poms (which are needed to build the dependency tree) from the internet. You could always try to ask some ICT crew (if they are capable enough...) about it at your company, maybe they have some useful hints.

right click on the project, Maven->Update Project->Tick "Force Update of Snapshots/Releases"

I had the same problem when I added a new dependency to pom.xml without network connection. After this, I had so many problems such as "Missing artifacts", "Missing Descriptor", or "Project Read error". I solved this
delete the bad dependency just added from local repository.
rebuild local index.
re-add the dependency

<properties>
<!-- ********************** -->
<!-- Plugin's properties -->
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<java.version>1.7</java.version>
</properties>
this pom setting worked for me

Usually this happens if there is a typo in the pom that Maven cannot understand and then it throws Project read error. Like in my case I copied a maven dependency snippet and I by passed the version. Instead of typing the actual version # it was getting it dynamically ${asciidoctorj.version} and my pom didn't have this in the properties section. So I got this error. Once I removed that and put a version number it started working.

I had this after copying a local repository folder from another machine. The fix was to go into the repository folder I copied and delete
_remote.repositories along with the 'LastUpdated' files then refresh the Maven dependencies in Eclipse (Alt+F5)

I faced same situation today. In my case it's caused by dependency name in wrong case. E.g.
Project A -> Project B -> Project C
In project B's pm file, I mistakenly specified the dependency artifacts name with "c" in stead of "C".
As in mac os, the files system is case insensitive. so I can build it in command line without detecting this mistake.
In Eclipse it breaks, but it provides very bad error message. In the error list, it says "dependency problem", but the name of dependency is empty. It also can't identify which line in the POM causes the problem.
When try to open "Effective POM" in POM viewer, it will show project read error. In the pop up error dialog box, it will show:
Could not read maven project
java.nio.channels.OverlappingFileLockException
All the messages are useless and misleading.
I finally detected this problem by submit to Jenkins CI after wasted hours of time.

I did maven clean install and the errors were gone

I faced the same issue of "Project read error" while clicking on "Dependency Hierarchy" tab. In my project I had a parent pom and child pom.
Parent pom had a property <appVersion>4.5<appVersion> that was being used in child pom
<version>${appVersion}<version>.
I selected the main project, right click and choose run as maven clean. The console display showed warning that version is using expression but should be a constant. Replacing ${appVersion} with constant value of 4.5 fixed the issue.