When running specific searches in SDL Trados Studio's Translation Memory view the following error is returned after some waiting time:

An error occurred when searching the Translation Memory. The TM may contain invalid Translation Units.

One or more errors occurred.
Response status code does not indicate success: 502 (Bad Gateway)
 

Note: The error occurs only for larger TMs (e.g. 200k TUs or more) and is more likely to occur if the text searched exists in only few translation units.

This issue was addressed with SDL Trados GroupShare 2017 SR1 CU08 (Cumulative Updates for SDL Trados GroupShare 2017 SR1) in combination with SDL Trados Studio 2017 CU13 (Cumulative Updates for SDL Trados Studio 2017 SR1) or SDL Trados Studio 2019 (SDL Trados Studio 2019 Release Notes).

Partial workarounds when using earlier releases of SDL Trados GroupShare 2017 SR1 or/and earlier releases of SDL Trados Studio 2017 SR1:

1. Increase Server Farm Proxy timeout in IIS

1. Open Internet Information Services (IIS)
2. Expand Server Farms
3. For all sub-nodes (eg. TMServiceFarm) make the timeout change under Proxy
4. Increase the timeout from default 30 to 60, 120 or even 180
   
   
   
   

• Increasing the timeout above approximately 100 seconds will have no effect on this particular issue.
• For very large translation memories, the problem is likely to persist for specific searches. In this case, the error details will be different - A task was canceled instead of Response status code does not indicate success: 502 (Bad Gateway)

2. Decrease Number of translation units per page

1. Go to File > Options > Translation Memories View
2. Reduce the Number of translation units per page

Further notes

• In some cases re-running the same search may avoid the error.
• The issue is more likely to occur if there are general performance issues on your GroupShare server. You may want to monitor for hardware bottlenecks - especially if you encounter with issue with TMs smaller than 200k TUs.