FreeFTPd module stopped

Today I noticed my SFTP sites are down, I remoted to the server and I got this dialog box onthe screen: FreeFTPd module stopped

When I restarted the service it works fine. I checked the event log and I got this error : Faulting application name: freeFTPdService.exe, version: 1.0.13.0, time stamp: 0x54b7fa61

Faulting module name: freeFTPdService.exe, version: 1.0.13.0, time stamp: 0x54b7fa61

Exception code: 0xc0000005

Fault offset: 0x000e75c0

Faulting process id: 0x1a6c

Faulting application start time: 0x01d68f68081f7992

Faulting application path: C:\Program Files (x86)\freeFTPd\freeFTPdService.exe

Faulting module path: C:\Program Files (x86)\freeFTPd\freeFTPdService.exe

Report Id: 44cdf399-0f15-4814-854c-852099be6256

Faulting package full name:

Faulting package-relative application ID:

Does anybody know what happened to my server? Thanks