EXPENG-E-TYP2 Query Server Error

[Hsiao]

Hi,

Does anyone know about the following Query Server Error?

[!]EXPENG-E-TYP2, The operation <assign> is invalid for data types <null> and <null>.[/!]

Details as follows

[!]Error number -239:

DMS-E-GENERAL, A general exception has occurred during operation 'prepare request with options'.
EXPENG-E-TYP2, The operation <assign> is invalid for data types <null> and <null>.[/!]

We upgraded to Impromptu 7.1 recently and all these errors started to occur. Thank you for any help you can provide!

Regards,
Hsiao