I recently upgraded my Trados 2019 version to Trados 2021 and I have a problem with importing packages for translation that my clients send to me (so far I only experienced this issue with .sdlppx files).

When I receive them by e-mail and try to open them (as I did before in Trados 2019), Trados starts running in another window even if another instance is already opened. When the program opens, nothing changes and the project list remains the same.

What baffles me is that all other .sdlppx projects that I have been sent before have this icon in front of them (I blurred the names for privacy reasons):

whereas the new projects that I am trying to open have this icon in front of them:

If I try to open the projects by saving them into a folder and then opening them with the "Open Project" command in Trados, I get this message:

Long story short, I don't know what else to try - if any of you have any ideas, I'd be eternally grateful because this is really starting to get on my nerves! The runaround I try is asking clients to send me .xliff files which I then import into projects by myself but this takes so much more time than just simply clicking on a link/file in your e-mail and I honestly don't have the time to do this with every single project I receive. Thank you all in advance!