Resolving Orphan Registry Keys from Uninstalled Office Versions

 

Removing Microsoft Office can leave orphaned registry keys, which may prevent DecisionTools Suite add-ins from working properly in Excel or Project. Symptoms include:

• "Application-defined or object-defined error"

• "Automation error: Library not registered"

• "Error in loading DLL"

• "Could not contact the Microsoft Excel application"

• "File name or class name not found during Automation operation"

• "Object variable or With block variable not set"

• Missing results or other graphs

 

Solution:

• Preferred: Edit the System Registry to remove outdated references (detailed instructions below).

• Alternative: If you cannot edit the registry or lack privileges, start Excel before opening DecisionTools Suite to bypass the issue.

 

Important

• Backup your registry before making changes.

• Only delete keys corresponding to versions you no longer have installed.

• Close Excel and Project before starting.

Steps to Edit the Registry

1. Open the Registry Editor

1. Click Start » Run, type REGEDIT, and click OK.

2. Remove Orphaned Excel Keys

1. Press Ctrl+F to open the search window.

2. Paste the following string (including curly braces):

   {00020813-0000-0000-C000-000000000046}
   

3. Check Keys and Match whole string only. Clear Values and Data.

4. Expand the key by clicking the + sign. Subkeys may include:

   • 1.5 → Excel 2003

   • 1.6 → Excel 2007

   • 1.7 → Excel 2010

   • 1.8 → Excel 2013

   • 1.9 → Excel 2016

5. Identify keys that do not match your installed Excel versions. If all match, skip deletion.

6. Optional Backup: Right-click the key, select Export, and save the file.

7. Right-click the orphaned subkey(s) (e.g., 1.5, 1.6) and select Delete. Confirm deletion.

8. Press F3 to search for other instances and repeat steps 4–7.

3. Remove Orphaned Office Keys

1. Press Ctrl+F to search for:

   {2DF8D04C-5BFA-101B-BDE5-00AA0044DE52}
   

2. Check Keys and Match whole string only. Clear Values and Data.

3. Expand the key by clicking the + sign. Subkeys may include:

   • 2.3 → Office 2003

   • 2.4 → Office 2007

   • 2.5 → Office 2010

   • 2.6, 2.7 → Office 2013 (2.7 may also be used for Office 2016)

   • 2.8 → Office 2016

4. Identify keys that do not match your installed Office versions. If all match, skip deletion.

5. Optional Backup: Right-click the key, select Export, and save the file (use a different name from Excel backup).

6. Right-click the orphaned subkey(s) and select Delete. Confirm deletion.

7. Press F3 to find other instances and repeat steps 4–6.

4. Additional Notes

• If you use @RISK with Microsoft Project, see Removing Outdated References to Project from the System Registry to remove Project references.

• After verifying that @RISK and other applications run normally, you can delete the saved .REG backup files.

Summary

By removing orphaned Excel and Office registry keys, you ensure:

• @RISK and other Lumivero products function properly

• Fewer conflicts between multiple Office/Excel versions

• Cleaner system registry