How to fix unstable continously synchronizing CrashPlan service


CrashPlan has been backing up my stuff for several years. Been very happy with it and it has already saved me from losing everything in a complete hard drive crash.

The last few months however it as been extremely unstable and never been able to complete a full backup. Which is very very bad. I've basically been stuck at 90% for a couple of months and the missing 10% in my case is over 100 GB. A lot of potential loss.


Contacted their customer support and after sending them my CrashPlan log files it turns out the poor CrashPlan service is a Java application and, by default, runs on a JVM limited to 512 MB of memory. Probably usually OK, but I have a lot of files. So basically the service has been garbage collecting itself to death these months and not gotten anywhere.

How to fix it

  1. Open an elevated command prompt.
  2. Stop the CrashPlan service.
C:\> net stop CrashPlanService
  1. Open the configuration file for the CrashPlan service.
C:\> notepad %ProgramFiles%\CrashPlan\CrashPlanService.ini
  1. Change -Xmx512M to for example -Xmx1024M or -Xmx2048M, depending on how much memory you have to spare.
  2. Start the CrashPlanService.
C:\> net start CrashPlanService

If your problem was lack of memory, it should now run more smoothly. Does for me anyways 🙂