[TYPO3-core] Could not acquire lock for ClassLoader cache creation

[Brian Lynch]

Running the install tool I can compare the database which is OK, 

If I try and "Clear all cache" then the system hangs and I get a file abandoned in typo3/Locks 0kb.

If I delete the abandoned file I can start over with the install tool. If I do not delete the file then I get the original error again.

Any thoughts on this?