RDS Farm with User Profile Disks - Error when sharing Office document

Hello,

i have some troubles with my RDS Farm and Office documents. I try to share a copy of a document that way.

Now Outlook opens and the following error message appears:

Translation: A process with a vulnerability has been exploited and is active.

Please can anyone tell why this error occurs?

Not entries are displayed in eventviewer.

I can't find anything about this error on google. (maybe my translation to English is wrong)

If outlook is already open before I share the file, it works without any problems.

My System:

1x Connection Broker

1x RDGateway

2x Session Hosts

Office 365

User Profile Disks activated

Thanks!

Martin