This started happening for me as well about ten days ago. I might have Outlook installed as part of the Office pack, but I do not use it. 

Yeah, I never use Outlook either, but I need Excel and Word. Ideally, RWS would at very least provide the option to disable Trados' integration with Outlook, since it can be buggy and many users simply never use it.

Knut Atle Klausen Anna Haxen Roberto Silveira rispal cristèle 
Now that I have a bit more context (THANK YOU) I did find an issue that had some light dev investigation work done on it.
Our reference for this is CRQ-6623 titled: Outlook setup starts unexpectedly during "create return package"

Please can everyone confirm what version of Studio they are using, including the CU.
Found under Help - About

Thank you!

Thank you for looking into it.

Mine is Trados Studio 2022 SR2 - 17.2.10.19084.

I updated to see if it would fix the problem. It didn't.

But when I uninstalled Outlook, create return package started working again, and it still works.

Trados 2022 SR1, in my case. It started happening with Trados 2022.

One important thing to notice: This isn't the same as a bug I've seen some people commenting where an Outlook window opens.

Normal behavior, if you have Outlook installed (even if you don't use it): When Trados creates a return package, it prepares to send it by e-mail. When that happens, the Outlook icon appears on the system tray and closes soon after, letting us close the return package window. It never opens an Outlook setup window.

Bugged behavior (only happens if you have Outlook installed, even if you don't use it): The Outlook icon does show up, but then it turns into a gray icon. Since I reinstalled Windows and can't screenshot it, I'll describe it: The normal Outlook icon (not the one shown above with the gear) turned gray. When you hover over it, it says "Outlook is closing." It only stops doing that if you close Outlook on the Task Manager. And I can't close the return package window or do anything in Trados until that is done. Once again, no Outlook window ever opens. I'm assuming that Trados waits for Outlook to close to make the package ready to send by e-mail but, as that never happens, it can't.

It would be enough if I could disable the integration with Outlook, as I never use it.

Trados 2022 SR1, in my case. It started happening with Trados 2022.

One important thing to notice: This isn't the same as a bug I've seen some people commenting where an Outlook window opens.

Normal behavior, if you have Outlook installed (even if you don't use it): When Trados creates a return package, it prepares to send it by e-mail. When that happens, the Outlook icon appears on the system tray and closes soon after, letting us close the return package window. It never opens an Outlook setup window.

Bugged behavior (only happens if you have Outlook installed, even if you don't use it): The Outlook icon does show up, but then it turns into a gray icon. Since I reinstalled Windows and can't screenshot it, I'll describe it: The normal Outlook icon (not the one shown above with the gear) turned gray. When you hover over it, it says "Outlook is closing." It only stops doing that if you close Outlook on the Task Manager. And I can't close the return package window or do anything in Trados until that is done. Once again, no Outlook window ever opens. I'm assuming that Trados waits for Outlook to close to make the package ready to send by e-mail but, as that never happens, it can't.

It would be enough if I could disable the integration with Outlook, as I never use it.