You are trying to access the properties page of a Project that has been converted from an Idea. Once you open the project, all the modules appear but the properties page throws a 500 error.
The app-ca.log file shows the error -
Cannot create a row of size <some number> which is greater than the allowable maximum row size of 8060.
The Idea does not throw an error when viewed and only a couple of modules throw the error in a project.
Database - MSSQL
MSSQL has a limitation on the row size of 8060 and there are too many custom attributes on the Investment object causing the error.
Deactivate enough attributes so that this limit is not reached.
Please note that this limit includes the data in these attributes, not just the attributes themselves so if you deactivate a chunk of custom attributes and still receive the error then you will either have to keep deactivating more or choose attributes with more data.