I am having this same problem and I cannot fix it. I tried going your suggestion of opening the Civil.chm from Windows explorer and letting it run through the install. Unfortunately, this did not do the trick. The strange thing is that I'm getting the install message for Land Desktop 2007, not Civil 3D, even though I'm opening the help from Civil 3D. Also, I was getting this problem in Land Desktop when I opened that help, but once I ran through the installer once, it went away. Any other suggestions??
Thanks,
Marissa Jenkinson
CADD Microsystems, Inc.
Marissa Jenkinson
CADD Microsystems, Inc.
Windows XP 64-bit
AutoCAD, Civil 3D, Map 3D, Raster Design 2011