The most common types of errors found when rendering reports are:

1) Invalid ConnectionString or RecordSource parameters. This usually indicates that the system could not open the specified database (a server may be off line, or a database file may be in a different location than what was specified) or that the SQL syntax used for the RecordSource property contains errors.

2) Error executing scripts or evaluating expressions. This usually indicates that the VBScript expression used contains a syntax error. In these cases, make sure you look at the exception message. It usually contains a good explanation of what caused the error.

Reference

C1Report Class
C1Report Members