error 1325 <username> is not a valid short File Name

This happens on file that is within a domain. From what I have seen so far this only happens with users that log in from a domain.

This solution is simple go to the following registry location in regedit:

HKEY_CURRENT_USER/Software/Microsoft/Windows/CurrentVersion/Explorer/User Shell Folders

Here you should change the personal registry key:

  • from \\<domain>\profiles$\<username>
  • to %USERPROFILE%\<username>

Note that User Shell Folders may exist in other locations as well, so you can search in the registry editor for User Shell Folders and correct all values you find, depending on your personal installation.

Then try to reinstall the program.

Another option is to create a new Admin User on your computer and install it that way.


To the original poster of this question, this fixes more than just .Net

I was fighting the same error installing AutoCAD, in an environment of GP's and Roaming profiles with locked out Local Admin accounts. (We are also in the process of migrating to Win7 from XP and having to install/test software) At one point months back I had to go into several registry profiles and hardcode the UserShellFolder because the prior Admin had created a Default User profile based on his profile which, of course, screwed up the pointers to the Personal settings and made it point to his User profile anytime a new user profile was created.

Also, you may need go into the Shell Folders in the same Explorer folder as mentioned above and tweak the profile references there too.


I had the same problem with the ArcGIS program and so I went back and looked at the Google forums in order to help someone :) I spent two days trying various ways to solve, including editing the registry values. I had uninstalled the program, but I think they were files that were not deleted.

I solved my problem with the program "Revo Uninstaller" (Free) by following these steps:

  • In the list of programs available for uninstallation, ArcMap (ArcGIS) was not showing up, but clicking the "Forced Uninstall" icon appears a field to enter the name.
  • I typed "Arc" and the program has appeared on the list.
  • I selected "Advanced" and "Next".
  • I selected all and deleted.
  • I clicked "Next" and finished.

After that, I managed to reinstall the program without any problem.