I too am experiencing this exact problem. Have a 2008R2 server with File Security 6.0.12035.0 installed and system locks up every 3 to 5 days. No BSOD just frozen up. Is a VM and machine performance graph shows CPU usage jumps up at time of crash and stays high until I do a hard reset of the VM. Memory usage stays normal throughout and disk usage stops at time of crash. Windows logs show nothing, ESET logs show nothing. Thankfully this is not a critical server. No issues with EFS version 6 on 2012 servers.