Outage in Gamma
Issues logging into Horizon with Webex
Resolved Minor
September 11, 2026 - Started 4 days ago
- Lasted about 5 hours
Incident Report
Summary AI Generated
Users experienced an "Invalid Requester" error when attempting to log into Horizon with Webex on 11th September 2026, affecting the General Network for approximately 4.8 hours. Engineers identified the root cause and worked with technology partners to implement a fix. The issue was fully resolved, with users able to regain access by pressing the back button and re-attempting login.
We can confirm that everything is now resolved.
If you press the back button in the top left corner and re attempt login it should work.
No further updates required. This notice will close at 20:00.
Issued 11/09/2026 17:25
Following on from our earlier update. Our engineers are continuing to work with our technology partners to implement a resolution.
A further update will be provided by 20:00 on Friday 11th September or earlier should more information be available in the meantime.
Issued 11/09/2026 16:34
Following on from our previous update, our engineers have identified the cause of the issue and are now looking to implement a fix.
A further update on this will be provided by 17:30 on Friday 11th September or earlier should an update be available in the meantime
Issued 11/09/2026 15:11
We are aware of issues whereby users are seeing the error message "Invalid Requester" when logging into Horizon with Webex.
Our engineers are currently investigating as a priority.
A further update will be provided by 4:30pm Friday 11th September or sooner should more information become available in the meantime.
If you press the back button in the top left corner and re attempt login it should work.
No further updates required. This notice will close at 20:00.
Issued 11/09/2026 17:25
Following on from our earlier update. Our engineers are continuing to work with our technology partners to implement a resolution.
A further update will be provided by 20:00 on Friday 11th September or earlier should more information be available in the meantime.
Issued 11/09/2026 16:34
Following on from our previous update, our engineers have identified the cause of the issue and are now looking to implement a fix.
A further update on this will be provided by 17:30 on Friday 11th September or earlier should an update be available in the meantime
Issued 11/09/2026 15:11
We are aware of issues whereby users are seeing the error message "Invalid Requester" when logging into Horizon with Webex.
Our engineers are currently investigating as a priority.
A further update will be provided by 4:30pm Friday 11th September or sooner should more information become available in the meantime.
Components affected
Gamma General NetworkTrusted by 1,000+ teams
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