We have the same issue with the two computers,
At my computer office, When we log onto ProjectWise, we can log on success and when we open file *.dng on that ProjectWise,
the following massage error alert:
Last Error 
Cannot start application for the specified document. Check your program associations.
Failted to generate managed workspace configuration file.
[WIN32 API #2147944126] The remote procedure call failed.
I wonder that, one machine was fix this issue when we go to control panel==> Program and Feature and do associate file with project wise by modify it, It got work.
But other one machine not working when we do like this.So we tried to log on ProjectWise with other account on this computer, it got working by we can open any *.dgn
I would like to get the real solution, what it the real issue? and please let me know the real resolution.
I think logging a Bentley service ticket is your best bet.
I would recommend first purging the user's working directory through the local document organizer, once that is done delete the user's working directory. What this will do is redownload the workspace and files giving the user a clean slate so to speak. Most of the times this fixes the issue at hand. If that does not resolve it please submit a issue with us and an analyst will help you get this resolved.