This bug was originally marked as duplicate of bug 147002, that is already resolved. This bug is still valid, so this seems to be another bug, but it might be related.
Build: NetBeans IDE Dev (Build 201307282300)
VM: Java HotSpot(TM) Client VM, 23.25-b01, Java(TM) SE Runtime Environment, 1.7.0_25-b15
gorrus: during the build
com.sun.tools.javac.jvm.ClassReader$BadClassFile: bad class file: package-info.class
unable to access file: /ssd/work/cnd-main/libs.junit4/external/junit-4.10.jar (No such file or directory)
Please remove or make sure it appears in the correct subdirectory of the classpath.
Created attachment 138173 [details]
From the attached messages.log file it seems that jar files on your ssd drive became inaccessible.
libs.junit4/external/junit-4.10.jar is an external dependency, can't it be rewritten during the clean/build?
still happens during external build
Created attachment 145005 [details]
The NB session had been open for a long time. I had opened and closed multiple project groups, compiling various projects throughout the day.
Towards the end of the day, the IDE became extremely slow while compiling a project and doing a background scanning.
This old bug may not be relevant anymore. If you can still reproduce it in 8.2 development builds please reopen this issue.
Thanks for your cooperation,
NetBeans IDE 8.2 Release Boss