Microsoft Addresses Outlook Crashing Issue due to “Out of Memory”Error

Microsoft has acknowledged a critical issue affecting Classic Outlook, where the application crashes upon encountering an “out of memory or system resources”error. This problem arises when users attempt to open more than sixty emails simultaneously.

Error Details Reported by Microsoft

In a recently published support article, Microsoft detailed the error message users might experience:

“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.”

Investigating the Cause of the Issue

The company is currently looking into the root cause of this out-of-memory (OOM) bug, which might involve a memory leak or an underlying issue, as it is uncommon for sixty emails to exhaust memory resources under normal operating conditions—particularly for systems with adequate RAM.

Workarounds Suggested by Microsoft

While a comprehensive fix is pending, Microsoft has proposed several workarounds for users who frequently open more than sixty emails as part of their workflow. These adjustments can be made through the Windows Registry:

Registry Key to Modify:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\WindowsNT\CurrentVersion\Windows\USERProcessHandleQuota

According to Microsoft, users can consider the following solutions:

1. Limit the number of simultaneously opened emails to sixty or fewer.
2. If opening more than sixty emails is necessary, adjust the USERProcessHandleQuota as outlined in this Microsoft documentation on User Objects. However, be cautious—altering this value could potentially destabilize your system as it allows all processes to utilize more user objects simultaneously, which may strain the operating system. The acceptable range for this setting is between 200 and 18,000, with a default value of 10,000 (Decimal, or 2710 Hexadecimal).

Where to Find More Information

For further insights and ongoing updates regarding this issue, refer to the official support article on Microsoft’s website: Outlook Errors When Opening Many Emails.

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