Why does running a report in Vault produce an Exceeded Character Limit error?
This error means there are too many columns in the report. The amount of space a column takes up in Vault depends on the data-type of the fields being used. An exact maximum number of columns for a certain report is different for each Vault.
This behavior must be resolved through trial and error by removing one column at a time until the report is able to run.
Vault Reporting Documentation: The Maximum Width for Report Columns