Just fixed this for a client of ours. Here's what worked for me.

1. Uninstalled all QuickBooks related programs using Revo uninstaller (free version). Chosing the Advanced scan and deleting any files/folder and registry items found.

2. Then I checked manually for any remaining Intuit folders in the following locations. Renaming them to foldernamebak (doesn't matter what you call it, only renaming to have as a temp backup)

%systemdrive%\Program Files

%systemdrive%\Program Files (x86)

%systemdrive%\ProgramData

%userprofile%\appdata\Local

%userprofile%\appdata\Roaming

3. Open up regedit and deleted the following keys (folders). Make sure to right-click the keys and export them if you're worried about breaking anything. You can re-import them if there's an issue.

HKEY_CURRENT_USER\Software\Intuit - if logged in as the user having the issue

HKEY_LOCAL_MACHINE\SOFTWARE\Intuit

If you're not logged in as the user for admin permissions then you can find the user under HKEY_USERS

You can check what folder it is from the following location in the registry

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\ProfileList\

Just need to scroll through the list of keys (folders) in that location and look for the one with the correct username. Should be under "ProfileImagePath"

4. Reboot, reinstall and test.