This trojan blocker ( MD5: aecf5532c99d4b5b51cd051513a8e505 ) prevents all software execution.
To remove the Trojan (and unlock windows), infected users need to enter a valid serial number.
According to VirusTotal the sample was detected by 9 Antivirus: https://www.virustotal.com/file-scan/report.html?id=daec186bb4512c56537ac1c0069ec3a36f3620f06997e5ebd0ae9f120d3a7290-1306610949
Unpacked was detected by 5 Antivirus and only NOD32 detect it as 'LockScreen': https://www.virustotal.com/file-scan/report.html?id=de60c9c33b72e7e9ca73aeb92dbc36cf9ed8a242d78bb0eac97b270a3e21c5e5-1306613233
Number to Call: 9670964964
Code to unlock Windows: WALKER