- Outlook patch (Build 19426.20218) broke “Encrypt only” emails and displayed unreadable attachments
- Workarounds: use Options tape encryption or revert to Build 19426.20186 via command prompt
- Microsoft has also disabled inline SVGs in Outlook for the web and new Outlook for Windows
Microsoft has released a new patch for classic Outlook, breaking how encrypted emails work. It’s currently working on a fix, and in the meantime, it offered a few ways to open encrypted emails in the popular client app.
In a brief update issued on January 6, Microsoft said that after updating to Current Channel Version 2511 (Build 19426.20218), email recipients may not be able to open “Encrypt Only” messages.
The bug manifests itself in the Reader Pane, where users may get a message that says “This permission-restricted message cannot be viewed in the Reader Pane until you verify your credentials. Open the item to read its contents and verify your credentials.”
Two solutions
After opening the email, users will find an attached message_v2.rpmsg and will not be able to read the content.
The problem occurs for users who encrypt the email using the settings under the email file dialog box (File > Encrypt), Microsoft further explained. To prevent the problem, there are two possible solutions. For the first, users should select the Settings ribbon, then select Encrypt and select Encrypt or Do Not Forward.
The other solution is to revert to a build before the problem started and then send the email. The problem started with build 19426.20218 and the next previous build that works is 19426.20186. To restore Office, users should open an elevated command prompt and run this command:
“%programfiles%Common FilesMicrosoft SharedClickToRunofficec2rclient.exe” /update user updatetoversion=16.0.19426.20186
Email is by far the most attacked vector, and the best communication platform for initial compromise. Microsoft frequently patches Outlook to close various holes and only recently changed how Outlook handles SVG images.
In a Microsoft 365 Message Center update, the tech giant said: “Inline SVG images will no longer appear in Outlook for the web or the new Outlook for Windows. Instead, users will see empty fields where these images would have appeared.”
Via Bleeping Computer
The best antivirus for all budgets
Follow TechRadar on Google News and add us as a preferred source to get our expert news, reviews and opinions in your feeds. Be sure to click the Follow button!
And of course you can too follow TechRadar on TikTok for news, reviews, video unboxings, and get regular updates from us on WhatsApp also.
