EnVision 4.1 Patch 10
We just finished completely re-imaging our ES-5060 and reinstalling 4.1 up to patch 9 after a disastrous patch 10 upgrade. We also upgraded to Java 1.7_17 at the same time, and can't say exactly what caused the problems on our system. In short, the contents of our \bin directory were completely lost. We had upgraded from an original 4.0 install, through many patches, 4.1, and more patches. It is suspected that something had gone wrong, but not caused any issues, many patches back.
We can't point directly to patch 10 as "the problem", but it cost us several days of rework so we'll be avoiding it for a while, probably jumping to the SP1 code stream at some point.