Solution to a strange Outlook glitch: read less emails

Microsoft Outlook might crash if you open too many emails. While Microsoft investigates the issue, it’s urging users to open fewer emails.

Microsoft Outlook team is investigating a worrisome issue that prevents users from opening more than sixty emails simultaneously.

Under the pressure of so many open emails, the program might slow down and crash, showing the following error messages in its last moments:

“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.”

“Out of memory or system resources. Close some windows or programs and try again,” reads another potential error message that might pop up to the user.

While Microsoft does not provide further information on what might be causing the issue or what the company’s next move is, a note on the Microsoft support page advises users to avoid opening sixty emails at the same time.

If the users still insist on reading sixty emails at once, the company offers a workaround to increase the process quota by navigating in Windows Registry to:

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

The value can be set to a number between 200 and 18,000. However, the company warns that increasing the process quota could lead to overall system instability. It enables all processes on the device to have more user objects open at the same time, placing additional strain on the operating system.

Opening an email could cause more than a crash

In June, Microsoft patched a critical vulnerability in the Outlook program that allowed threat actors to execute malicious code on user machines. The vulnerability affected most Outlook email clients.

Cybersecurity experts from Morphisec Threat Labs, who first reported it to Microsoft in April, have warned that the vulnerability opened gates to potential data breaches, unauthorized access, and other malicious activities, including a full system compromise.

Attackers can exploit the vulnerability to run arbitrary code on affected systems by simply sending an email. To trigger the attack, the user needs to open the email, which is quite easy prey, as Microsoft Outlook has an auto-open email feature.