
Copilot Studio GCC Agent Suddenly Fails with SystemError When Attaching Documents + Missing File Upload Settings
Hello,
I am experiencing an issue with a Copilot Studio agent running in a GCC environment.
Whenever a user attaches a document in the chat, the agent immediately fails with:
Sorry, something went wrong. Error code: SystemError
The failure occurs before any topic is activated. No trigger phrases or topics execute. Without attachments, the agent works normally.
Environment type: GCC
Agent works correctly with normal text prompts
Failure happens only when a document is attached
The test chat briefly shows “Generating plan” and then throws the SystemError
No topic activation occurs
This issue started recently
A couple of weeks ago, attachments were working correctly without any issues
No major changes were made to the agent configuration before the issue started
The setting to enable or disable file attachments is missing from the agent settings.
According to Microsoft documentation, there should normally be a setting similar to:
Settings → Generative AI → File processing capabilities → File uploads
However, this option does not appear at all in the GCC environment.
Are file attachments currently supported in GCC Copilot Studio environments?
Is there a feature flag or admin setting required to enable attachment support?
Is the missing “File uploads” setting expected behavior in GCC?
Has anyone else experienced SystemError failures before topic activation when attaching files?
Could this be related to a recent platform update or regression affecting GCC tenants?
Any guidance would be appreciated.