I am guessing that computer is pointing to a different Medisoft Root Data Path than the other computers. Double-click the bottom bar of a computer that is working and it should display \\<server name>\Medidata\<practice folder name> on the bottom bar
Now go to the computer that isn't working and press and hold the F7 key while starting Medisoft. It will prompt you for a new root data path. Browse to \\<server name>\Medidata to match what is displayed on the computer above.
If that doesn't get it, then my second guess would be an improper firewall setting on the computer that isn't working. Try disabling the firewall.
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