Error - Installing Office customization. There was an error during installation

Problem

After upgrading the Outlook adding this error can occur. It usually occurs due to Outlook being open during the installation.

Solution

1. Restart the PC 
2. Make sure LawMaster and Outlook at not running 
3. Uninstall the LawMaster Outlook Addin 
4. Restart the PC 
5. Open Outlook and check the Addin is no longer installed: 
   1. Go to Outlook > File > Options > Add-ins 
   2. Check that the LawMaster Add-in is not list in the Active, Inactive or Disabled lists 
6. Restart the PC 
7. Make sure LawMaster and Outlook at not running 
8. Reinstall the LawMaster Outlook Addin 
9. Restart the PC 
10. Start LawMaster and Outlook

If the above doesn't resolve the issue then you will need to copy the following registry key from a PC that the issue isn't happening on to the affected PC(s): 

• Computer\HKEY_CURRENT_USER\Software\Microsoft\Office\Outlook\Addins\LawMaster.OutlookAddIn

NOTE: If you are having trouble or unable to uninstall the Microsoft Office Outlook add-in, try removing it through the troubleshooting tool that can be downloaded from the following link:

• Fix problems that block programs from being installed or removed