(FYI, that actually wasn’t my error message.)
I’m sure CrashPlan engineers have a good reason for solving these problems by jumping right into a complete uninstall/re-install. BUT, you might try increasing the memory first. That worked for me:
java mx 3072,restart
The symptoms I saw were CrashPlan Tray disappearing a couple minutes after booting Windows and also the CrashPlan app closing a couple minutes after opening, while scanning for files to back up.
I read the above support article from CrashPlan, decided to try just upping the memory, and that seems to have worked.
I got this after adding a huge Drobo volume to the backup set. I presume that’s what caused the problem. The huge increase in the number of files caused CrashPlan to exhaust its allocated memory.