'All of a sudden', in 2005, I am getting an access exception error in wd_dwg.arx, and the command line returns "ADS request error". This is happening when I try to do a retag/update on any source or destination symbol on any drawing.
It also happens if I try to rebuild the project database.
One of my project drawings had become seriously corrupted somehow.
I just tried removing the corrupt file from the project, and this 'fixed' the project. The corrupt drawing was causing any project-level operation, such as retag/update and rebuild database, to fail with Unhandled Access Violations. Replacing the corrupt file with a version from our server backups essentially solved the problem and restored the corrupt drawing.