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Is the Frustrating Outlook Startup Crash Finally Over?
For weeks, many people using the classic version of Microsoft Outlook have experienced a persistent issue where the program crashes immediately upon starting. This problem occurred when Outlook tried to connect to an Exchange Online email account. Microsoft has now rolled out a fix to resolve this.
Understanding the Problem
If you were affected, the program would stop working right after you tried to open it. This was often accompanied by a specific error message on your screen. The message would state: “Cannot start Microsoft Outlook. Cannot open the Outlook window. The set of folders cannot be opened. The attempt to log on to Microsoft Exchange has failed.”
This issue was traced back to a problem with how Outlook authenticated, or signed in, to the Exchange Online service. Before the fix, the official advice was to use the web version of Outlook or the new Outlook for Windows client. To solve the problem for the classic desktop app, your IT department had to open a support case with Microsoft, which was a slow and indirect process.
The Solution is Here
On October 20, 2025, Microsoft updated the status of this bug to “Fixed.” The company’s service team has applied changes on their end that correct the root cause of the issue.
What this means for you:
- You do not need to install any updates yourself.
- The fix is applied automatically through the service.
- The classic Outlook client should now start correctly without crashing.
Microsoft is currently monitoring the situation to confirm the fix has worked for all users. If you were previously having this issue, your Outlook should now function as expected.