If your folder "My Documents" is on a network drive, you may get the error message "Unable to open the user data folder! Please reinstall Out of the Park Baseball." You don't actually have to reinstall, but OOTP can't support data stored on network drives.

The solution is to move your OOTP data to your local machine. Use the following steps to move your OOTP 9 user data from a network drive to a local machine.:

1. Close OOTP 9
2. Locate the folder \My Documents\Out of the Park Developments\OOTP Baseball 9
3. Copy the whole contents of that folder into the clipboard (Ctrl+A to select everything; Ctrl+C to copy)
4. Create a folder on a local drive, for example C:\OOTP9
5. Open that folder, and paste the data from the clipboard (right click into the folder and select "Paste"). Windows will copy all the data files to C:\OOTP9. You should have a folder C:\OOTP9\data then.
6. OK, now we need to tell OOTP to open the data from that folder. Open the Windows Start menu, click on "Run", enter %appdata%\Out of the Park Developments\OOTP Baseball 9\data\config and hit Enter. This should open a folder with some config files in it.
7. If there is a file called "paths" already there, open it with Notepad or another text editor. If there is no such file, right click in the folder, select "New --> Text Document." Call the file "paths" (with no .txt extension), and open it in Notepad.
8. In the first line, write "path_user_data" and hit enter, in the second line write the path like this one: C:\OOTP9\data. So the file should look like this:

path_user_data
C:\OOTP9\data

     9. Close and save it and restart OOTP