1. Check for a hung instance of Microsoft® Excel®.
   1. Close all Microsoft® Excel® files.
   2. Right-click on the Task Bar and select Task Manager.
   3. Click on the Processes or  Details tab and sort by Name.
   4. Right-click and choose End Process on any excel.exe processes.
2. Replace the epace.xla addin.
   • How to replace the Microsoft® Excel® add-ins for CCH® ProSystem fx® Engagement or Workpaper Manager.
3. Rename the excel##.xlb file.
   • How to rename the excel##.xlb file.
4. Open Microsoft® Excel® outside of Engagement.
5. Go to File > Options > Addins and verify that epace.xla and pfx.ribbon.exceladdin are active. If it is disabled, re-enable it.
   • How to enable the Microsoft® Excel® add-ins for CCH® ProSystem fx® Engagement or Workpaper Manager.
6. Add Workpapers to Microsoft® Office® Trusted Locations.
   1. Open a Microsoft® Excel® workbook and click File > Options > Trust Center > Trust Center Settings.
   2. Click Trusted Locations > Add New location.
   3. In the Path box, enter C:\Pfx Engagement\WM\Workpapers\.
   4. Select the check box Subfolders of this location are also trusted.
   5. Click OK.
   6. Select the check box Allow Trusted Locations on my network (not recommended).
      • While the option is listed as "not recommended", if users are working with Microsoft® Excel® workbooks that originated on a network location, or linked from a network location, this option is required for functionality.
7. Disable Protected mode.
   1. Open a Microsoft® Excel® workbook and click File > Options > Trust Center > Trust Center Settings.
   2. Click Protected View, and clear all check boxes.
8. Set the Macro Settings.
   1. Open a Microsoft® Excel® workbook and click File > Options > Trust Center > Trust Center Settings.
   2. Click Macro Settings and select Disable all macros except digitally signed macros.
9. Make sure that the user has appropriate rights to the folders in Microsoft® Windows®.
   • How to find the folder permissions that are required for CCH® ProSystem fx® Engagement or Workpaper Manager. 

Note: These steps are for troubleshooting issues that happen on all Microsoft® Excel® workpapers. If the error occurs in only one workpaper in a binder, then these steps will probably not resolve the issue.