Outlook will crash if you open too many emails at once. Here’s why

Microsoft’s mail app is currently struggling with two problems. For a few days now, Outlook users haven’t been able to use the Ctrl + C keyboard shortcut to copy text in emails, otherwise the app freezes.

Now, another issue has cropped up: Outlook is crashing when many different emails are opened at once. Microsoft is aware of both problems and currently working on permanent fixes for both. Fortunately, while waiting for those fixes, you can use a temporary workaround.

Outlook crashes with too many emails

According to Microsoft’s support page on the issue, Outlook is crashing when more than 60 emails are opened at the same time. Doing so apparently overloads working memory, causing the app to crash.

You’ll either see this error message:

“Sorry, we’re having trouble opening this item. This could be temporary, but if you see it again you might want to restart Outlook. Out of memory or system resources. Close some windows or programs and try again.”

Or this error message:

“Out of memory or system resources. Close some windows or programs and try again.”

Microsoft is currently trying to find out exactly why this is happening. It shouldn’t happen too often as it’s rare to keep so many emails open at any given time, but you should avoid doing so for the time being.

If you still need a quick solution, Microsoft recommends making changes to the Windows registry in order to increase the number of processes allowed at the same time. However, this can affect the stability of your system, so we don’t recommend this.

Outlook crashes when copying text

In the older version of Outlook, there are still problems with the text-copying action. If you use the Ctrl + C keyboard shortcut, the app may hang, as described on the official support page.

To solve the problem, you have two options: Switch to an earlier version of Outlook in which the error wasn’t yet present, or switch to the new Outlook, which can be found in the Microsoft Store here.

If you want to revert to an earlier version of classic Outlook, check out our previous coverage of this issue for instructions on how to do that.

Further reading: Key details to know about the new Outlook app