New to Telerik Report ServerStart a free 30-day trial

BadImageFormatException or Architecture Mismatch message when using ODBC connection

Updated on Jan 28, 2026

Environment

ProductProgress® Telerik® Report Server
Operating SystemWindows
Target Framework.NET Framework 4.6

Description

When the Report Server application is running in 32-bit application pool and opens an ODBC connection that uses a 64-bit driver, the ODBC Driver Manager throws either a BadImageFormatException(reproduced with Oracle driver) or shows an The specified DSN contains an architecture mismatch between the driver and the application error message (reproduced with Progress® OpenEdge® driver).

The same is valid also if the Report Server is running in 64-bit application pool and ODBC uses a 32-bit driver.

Solution

If the correct version of database drivers is installed, then the Report Server's application pool should be set to run in different mode (32 or 64-bit).

The Report Server's application pool settings define it as a 64-bit application by default. To change it:

  1. Navigate to the Report Server's application pool in the IIS Manager
  2. Open its Advanced Settings form and look for a Enable 32-bit Applications property
  3. Change it to False to run the Report Server instance in 64-bit mode and recycle the pool.
In this article
EnvironmentDescriptionSolution
Not finding the help you need?
Contact Support