I'm pretty sure it's calibre 0.8.7 (see attachment). Further, it seems my version (which I picked up and installed yesterday) is very problematic. It just crashed for the second time during a field edit (title field)...
Faulting application name: calibre.exe, version: 0.8.7.0, time stamp: 0x4e050eaf
Faulting module name: python27.dll, version: 2.7.1150.1013, time stamp: 0x4cf1405f
Exception code: 0xc0000005
Fault offset: 0x00001632
Faulting process id: 0xd60
Faulting application start time: 0x01cc37db0e5ff542
Faulting application path: C:\Program Files (x86)\Calibre2\calibre.exe
Faulting module path: C:\Program Files (x86)\Calibre2\DLLs\python27.dll
Report Id: a116a608-a3e4-11e0-a19c-d55cd5986d11
Fault bucket 2501922651, type 1
Event Name: APPCRASH
Response: Not available
Cab Id: 0
I think I'm going back to version 0.8.6 which worked fine without any problems. Unless you have some idea's I can test?