​Microsoft is investigating a known issue that affects Microsoft 365 customers and causes Classic Outlook to crash or hang when copying text.

These issues appear on systems running Outlook Current Channel version 2409 (Build 18025.20096) or higher or when using languages ​​with an IME (Input Method Editor).

“When you select text in a classic Outlook email and then use the Ctrl+C copy shortcut, Outlook may crash or hang”, Microsoft explain.

Redmond says its Outlook team is investigating this newly recognized issue and will provide more information when mitigations or a fix become available. Until a solution is found, the company is offering affected customers several temporary fixes to work around the issue.

They can revert to a previous version of the Input Method Editor using the detailed instructions available on the website. Roll back to a previous version of an IME support page.

This requires opening the Settings app, searching for “IME Settings”, selecting their language’s IME settings, clicking General, and enabling the “Use previous version of Microsoft IME” option.

Microsoft also advises those affected to revert to the previous version of Outlook, which is not affected by this known issue.

To do this, search for Command Prompt in the Windows search box, right-click the “Command Prompt” icon, and then click Run as administrator. Next, paste the following commands into the Command Prompt window that appears and press Enter after each one:

cd %programfiles%\Common Files\Microsoft Shared\ClickToRun
officec2rclient.exe /update user updatetoversion=16.0.17928.20156

In September, Microsoft also fixed a bug that Microsoft 365 apps crashing like Outlook, Word, Excel and OneNote when typing or spell checking text.

A month earlier, the company shared temporary solutions for more well-known issues, including one which triggered Problems signing in to Gmail for classic Outlook users and caused Outlook crashes after opening.