Microsoft Warns: Opening Too Many Emails in Outlook May Cause Crashes

Microsoft has warned Outlook users about a potential crash when opening a high number of emails simultaneously in the application.

Following multiple user reports about issues in the Outlook email client—particularly in the Classic version—Microsoft has confirmed that opening 60 emails at once will cause the program to stop functioning properly.

If this issue occurs, users may see an error message related to memory, which signifies a performance limitation in Outlook. This limitation makes it difficult to multitask and manage large amounts of information quickly, especially when attempting to open multiple emails at the same time.

According to Microsoft, users might encounter one of these messages when the problem arises: "Sorry, we're having trouble opening this item. This might be temporary, but if you see it again, you might want to restart Outlook," or "You're out of memory or system resources. Close some windows or programs and try again." If you receive one of these messages, it's likely an Outlook performance issue, not a problem with your computer's RAM.

Microsoft recommends restarting the application if any of these errors appear and has noted that a permanent fix is in progress. For users who need to open more than sixty emails at a time, Microsoft suggests a workaround: adjusting the USERProcessHandleQuota, which controls the number of user objects Win32 applications can open. Increasing this quota may provide some relief but can also impact overall system stability by placing additional load on the operating system.

The value for USERProcessHandleQuota can range between 200 and 18,000, with the default set at 10,000 (represented as 2710 in hexadecimal). However, Microsoft cautions that this change should be used carefully, as it may affect system performance.

In addition to these issues, Microsoft reminds users to keep their Outlook and Windows software updated, as performance problems are sometimes related to outdated versions. Regular updates often include patches that optimize resource management and improve the application's handling of large workloads. This is especially important for users who rely on Outlook for business, where managing multiple emails efficiently is essential. Microsoft is also exploring ways to optimize memory usage within Outlook, and users can expect future updates that may reduce the need for workarounds when managing a high volume of emails.