EPM2007 – Cube Building Error message ‘GetJoinForCustomFieldDimension’

I recently came across an issue whereby the Data Analysis Cube build service failed with the following message;

‘Failed to build the OLAP cubes. Error: Invalid call to GetJoinForCustomFieldDimension. Cannot join "Task Non Timephased" fact with a custom field of entity Assignment’

The cube was building fine up to a point when some attributes where updated in the system and assignment dimensions where updated. This caused the reporting database to refresh and the subsequent Cube Build process to fail. I resolved the issue by following these steps;

1. Restarted the SQL Server (also housing Analysis Services). The Temp DB had ‘bloated’. 
2. Remove all the cube dimensions and measures via Server Settings > Cube > Configuration.
3. Save Cube Configuration
4. Add back the required cube dimensions and measures.
5. Save Cube Configuration
6. Rebuild the Cube

Voila! Back to normal again.

Note: I did go a couple of steps further after step (1) above to manually delete the Analysis Services Database (this gets re-created automatically by cube building service) and also re-created the OLAP Repository SQL Database. I just wanted to start clean!

Hope this helps others in the same boat.