workspace error, system crash

[robershottea]

AutoCAD 2010 civil 3D.

Main issue is frequent crashes of the AutoCAD software. Sometimes 10-12 time's in a day. Unfortunately their are no error messages, and I have yet to see any pattern in when and how it crashes.

The problems I can see are the workspace, and process memory of my system. The workspace does not load correctly. The Ribbon shows multiples of the every tab at least twice. All tabs show the commands but not the pictures associated with the commands. CUIload shows correct workspaces. 

Second note is that my system runs the same .dwg file's at 2/3 the processing memory than any other identical systems I run AutoCAD on.

Third, through my digging and attempted solutions I found that the AcSignCore_.dll file was missing.

I have: re-installed 3D twice, updated graphics drivers on my system and run open close save hotfix as well as AutoCAD2010 update 2 for 64 bit system.

[pendean]

Turn off hardware acceleration in C3D, or turn it on if it is off: problem go away?

[jggerth1]

WinXP 64bit, or Windows7 64 bit?

Might just be time to Fdisk the drive, reformat, and reinstall everything from scratch.

[dgorsman]

AutoCAD, or Civil3D?  They are similar but different.