KB439108: Internal error: GetMSTROfficeString() - error formatting resource string MOZ_PRODUCT_NAME (Object reference not set to an instance of an object.) appears when opening Microsoft Office in MicroStrategy 10.4 Hotfix 5 and MicroStrategy 10.9

SYMPTOM
After installing Strategy 10.4 Hotfix 5 or Strategy 10.9, some users get a pop-up window with an error when opening a Microsoft Office product. The error can occur in different Microsoft Office products and not appear in others. The error disappears after clicking OK and Microsoft Office can be used normally.

 
Internal error: GetMSTROfficeString() - error formatting resource string MOZ_PRODUCT_NAME (Object reference not set to an instance of an object.)
STEPS TO REPRODUCE

1. Install Strategy 10.4 Hotfix 5 or Strategy 10.9
   
2. Install Microsoft Office
   
3. Open a Microsoft Office product
   
4. The error may appear
   
5. The error may also appear when navigating to File > Options > Add-Ins
   

CAUSE
This is an identified defect in Strategy 10.4 Hotfix 5 and Strategy 10.9. It is caused due to registry setting changes in the machine for one or various Microsoft office products. These registry setting changes may be changed due to an update on the machine. It is not system specific.
ACTION
This issue has been addressed in 10.4.7 . Upgrade to this version to take advantage of this fix.
WORKAROUND
1. Go to Start à Run, type regedit and press enter
2. The 'Registry Editor' window will open
3. Navigate to HKEY_CURRENT_USER  à  SOFTWARE  à  MICROSOFT  à   OFFICE  à Excel (or PowerPoint or Word) à   Add ins à MozartAddIn. MozartAddIn
​

4. Double click on 'LoadBehaviour' and set the Value data to 3. Click OK

If the above steps do not resolve the issue, there is one additional workaround:

1. Navigate to C:\Users\ “username” \AppData\Roaming\MicroStrategy\Office.
2. Delete the Office folder.
3. Relaunch your Office application. The Office folder is recreated with the correct moimain.dll.config file.

WARNING
Some users reported the error happening in Strategy Office 10.4 HF8, 10.10 and 10.11
For now, the better solution is to rollback to 10.4 GA version of te plugin, where no such an error was seen. You can use the older plugin to connect to newer versions of Strategy. The new Office plugin will resolve this kind of flaws, as it will integrate better with Office 365.
KB439108