Will Power Automate emails crashes Outlook 2019?

[German]A blog reader contacted me with a crude observation. In his customer environment, there is a case with Office 2019 in which emails sent by Power Automate cause the recipient's Outlook client to crash. Is this an isolated case or are there more people affected?

Emails from Power Automate

You can use Microsoft's Power Automate to create email flows to send, receive or process emails automatically. The technical term for this is Power Automate flows. For example, flows can be created that automatically send emails when new data is added to a list or forward emails when a new email is received.

The last time I wrote about the topic of Power Automate  was in the German blog post Microsoft PowerAutomate meldet potentielle Abschaltung "wegen Nichtbenutzung" . Power Automate seems to be used more frequently – and in times of AI agents, the topic of automatic mail notifications for event X could increase. So much for the following observation.

Strange Outlook Classic behavior

Blog reader Bernd W. contacted me by e-mail on June 2, 2025 and described a crude problem under the subject "Strange Outlook behavior". He has a customer who uses Microsoft's Power Automate to automatically send notification emails in flows.

The recipient of this email is using Microsoft Outlook 2019 (from a volume license). The Office 2019 package was up to date with the latest patch, the reader wrote. The emails sent by Power Automate are delivered to the customer's Outlook 2019 clients via a Microsoft 365 tenant. The reader states that Business Premium is licensed for the MS 365 tenant.

The problem: As soon as a notification email from Power Automate arrives at the Outlook 2019 client via the MS 365 tenant, the program crashes and closes. In the event display, there is only the usual AppCrah note (see screenshot below), which leads nowhere.

According to the blog reader, there is nothing useful in the WER file either. All add-ins were then deactivated for testing purposes, but to no avail. And the crashes also occur in safe mode.

The reader also noted that in the mode in which Outlook 2019 is started normally, it is sufficient if the mail is displayed in the preview. This is the case, for example, if the Power Automate mail is the first entry in the message list of the inbox and should then be displayed in the preview. The Outlook client then crashes immediately.

The problem exists on several computers. A very fresh client with Windows 11, which was set up last week (i.e. at the end of May 2025), also shows these crashes. The reader said: "Perhaps several people are experiencing this." After publishing the German version of this article, some user came back with similar experience. Hence my question: Has anyone else experienced this?

Possible root causes

Searching the Internet results,  that when a Power Automate flow sends e-mails that are received in Outlook, various factors can lead to crashes. Damaged Outlook profiles, add-ins or problems with the actions of the flow are mentioned.

I would rule out damaged Outlook profiles due to "several affected clients". Add-ins were ruled out as the cause by using safe mode. According to Internet advice, troubleshooting includes checking for updates (not very helpful with the current patch status), deactivating add-ins, repairing Outlook (can be ruled out as a solution).

That leaves "ensuring that the PowerAutomate flow configurations are correct". Would indicate an individual problem – but brings me to the question "how shaky is this construction that even a simple email sends our IT solutions to digital nirvana".

During a search, I came across the MS Answers forum post Crashed Outlook because of a loop, where Outlook was probably driven to "digital death" by a loop in the Power Automate flow. The flow was deleted by the person concerned, which did not stop the mails. The post is from mid-April 2025, there is no solution there. Anyone else with an idea or even a solution?