gcasDtServ.exe continually reads gcDeterminationData.gcd

[Guest]

After my system has been up for a while, the gcasDtServ.exe process goes into
a mode where it continually reads the file gcDeterminationData.gcd. It uses
5-10% of the CPU and makes the mouse cursor flash between the normal and wait
states. It reads the entire file between the offsets 0 and 674999 in about 2
seconds waits 2 seconds, then does it again. The problem persists until I
reboot the system. It reads 33 bytes, 4 bytes, 4bytes, 2bytes, then repeats
the sequence. Here is partial log from filemon:
293457 9:37:12 PM gcasDtServ.exe:3240 READ C:\Program Files\Microsoft
AntiSpyware\gcDeterminationData.gcd SUCCESS Offset: 124 Length: 33
293458 9:37:12 PM gcasDtServ.exe:3240 READ C:\Program Files\Microsoft
AntiSpyware\gcDeterminationData.gcd SUCCESS Offset: 157 Length: 4
293459 9:37:12 PM gcasDtServ.exe:3240 READ C:\Program Files\Microsoft
AntiSpyware\gcDeterminationData.gcd SUCCESS Offset: 161 Length: 4
293460 9:37:12 PM gcasDtServ.exe:3240 READ C:\Program Files\Microsoft
AntiSpyware\gcDeterminationData.gcd SUCCESS Offset: 165 Length: 2
293461 9:37:12 PM gcasDtServ.exe:3240 READ C:\Program Files\Microsoft
AntiSpyware\gcDeterminationData.gcd SUCCESS Offset: 167 Length: 33
293462 9:37:12 PM gcasDtServ.exe:3240 READ C:\Program Files\Microsoft
AntiSpyware\gcDeterminationData.gcd SUCCESS Offset: 200 Length: 4
293463 9:37:12 PM gcasDtServ.exe:3240 READ C:\Program Files\Microsoft
AntiSpyware\gcDeterminationData.gcd SUCCESS Offset: 204 Length: 4
293464 9:37:12 PM gcasDtServ.exe:3240 READ C:\Program Files\Microsoft
AntiSpyware\gcDeterminationData.gcd SUCCESS Offset: 208 Length: 2

 

[Dave M]

Hi Carl;
gcDeterminationData.gcd is one of the 3 files that make up the signature
definitions in MSAS and is refreshed weekly via File > Check for updates. I'd
attempt to update the definitions first, and if that doesn't work then try a
repair install of MSAS. Has this been happening for a while or just after last
week's update on December 15? It sounds like your signature database has broken
and needs to be rebuilt either through an update or a repair of the program
itself in Add/Remove.