Users may have received no response when prompting Microsoft 365 Copilot Chat using the Claude Opus model

Title: Users may have received no response when prompting Microsoft 365 Copilot Chat using the Claude Opus model User impact: Users may have received no response when prompting Copilot Chat using the Claude Opus model. More info: When users attempted to prompt Copilot Chat using the Claude Opus model, they may have received an error that stated, "We're experiencing high demand. Please try again later." Final status: After applying our configuration changes to rebalance request traffic, we've confirmed after a period of monitoring that the issue was successfully resolved. Scope of impact: Any user prompting Copilot Chat using the Claude Opus model may have been impacted. Start time: Monday, June 01, 2026, at 1:00 PM UTC End time: Thursday, June 04, 2026, at 9:00 PM UTC Root cause: An increase in request traffic was causing the portion of infrastructure responsible for facilitating the responses to prompts using Claude Opus in Copilot Chat to operate in a suboptimal state. Next steps: - We're reviewing opportunities to improve our monitoring and alerting for high request traffic scenarios to improve response time and better prevent similar future impact. This is the final update for the event.

Title: Users may receive no response when prompting Microsoft 365 Copilot Chat using the Claude Opus model User impact: Users may receive no response when prompting Copilot Chat using the Claude Opus model. More info: When users attempt to prompt Copilot Chat using the Claude Opus model, they may receive an error that states, "We're experiencing high demand. Please try again later." Current status: We've applied configuration changes to rebalance the request traffic and are monitoring our service health telemetry to confirm whether the impact is remediated. Scope of impact: Any user prompting Copilot Chat using the Claude Opus model may be impacted. Start time: Monday, June 01, 2026, at 1:00 PM UTC Root cause: An increase in request traffic is causing the portion of infrastructure responsible for facilitating the responses to prompts using Claude Opus in Copilot Chat to operate in a suboptimal state. Next update by: Friday, June 05, 2026, at 6:30 PM UTC

Title: Users may receive no response when prompting Microsoft 365 Copilot Chat using the Claude Opus model User impact: Users may receive no response when prompting Copilot Chat using the Claude Opus model. More info: When users attempt to prompt Copilot Chat using the Claude Opus model, they may receive an error that states, "We're experiencing high demand. Please try again later." Current status: We've identified that an increase in request traffic is causing the portion of infrastructure responsible for facilitating the responses to prompts using Claude Opus in Copilot Chat to operate in a suboptimal state. We're evaluating our options to rebalance the request traffic and remediate the impact. Scope of impact: Any user prompting Copilot Chat using the Claude Opus model may be impacted. Root cause: An increase in request traffic is causing the portion of infrastructure responsible for facilitating the responses to prompts using Claude Opus in Copilot Chat to operate in a suboptimal state. Next update by: Friday, June 05, 2026, at 12:00 AM UTC

Title: Users may receive no response when prompting Microsoft 365 Copilot Chat using the Claude Opus model User impact: Users may receive no response when prompting Copilot Chat using the Claude Opus model. More info: When users attempt to prompt Copilot Chat using the Claude Opus model, they may receive an error that states, "We're experiencing high demand. Please try again later." Current status: We're reviewing provided HTTP Archive format (HAR) logs to gain clarity on the issue and determine the next steps to isolate the root cause. Scope of impact: Any user prompting Copilot Chat using the Claude Opus model may be impacted. Next update by: Thursday, June 04, 2026, at 10:00 PM UTC

Title: We're looking into a potential problem impacting Microsoft 365 Copilot Chat User impact: We're checking for potential impact to your users. Current status: We're investigating a potential issue impacting Microsoft 365 Copilot Chat and checking for impact to your organization. We'll provide an update within 30 minutes.