Your computer has been severely infected by malware, that is JMMARK2.DAT. This is quite dangerous and unsafe for your PC and there may be other infections on your PC. You should urgently check your PC and remove any malicious application including JMMARK2.DAT as soon as possible.

Location : C:\WINDOWS\jmmark2.dat
Type : Malware
Dangerous : YES
Removal : Immediately

 
How to get rid of JMMARK2.DAT