Edit: I didn't know what that specific error was so these instructions are generic... Obviously I'd go with Alexander's Suggestion first.
Whenever I have this type of an issue on a support call I always start with a few basic troubleshooting steps to determine where the issue is.
I'd first go log in on that problematic PC as a different windows user and try the same thing (using that different userid in laserfiche too)
Then I'd have the user with the issue log in on a different PC in the office under her username and laserfiche login and try.
If the 2nd user has an issue on her machine, it's probably something with the client and/or her installed PDF program. I'd uninstall acrobat and the client and reboot, then reinstall both.
If a 2nd user is able to log in on the problematic machine and work fine and the user who is having an issue has no issues on machine #2 and it works fine then it's probably that user's windows profile.
If a 2nd user is able to work fine on the problematic machine and the person with an issue has trouble on a 2nd machine then it's probably a corruption in the user's laserfiche attributes. If so, I'd clear them by going into admin console, right clicking the user and choosing properties, then go to the attributes tab and clear everything.
These issues are always the harder ones to determine but hopefully these steps will give you something to start with.