Hello Omri Ofek Luzon ,

When posting a question in Community- it's always a good idea to post as much information as you possibly can- along with the full error stack.

https://community.sdl.com/product-groups/translationproductivity/w/customer-experience/4159/how-to-get-help-quickly-in-the-sdl-community-technical-forums

First of all- please download and save the client package to your local c drive and save in a folder.

Ensure that any resources you have, are locally stored and not maybe on the D drive or other external drives.

Now open Studio and click open package and direct Studio to this package (don't double click the package to open Studio).

Does this now open?

If not- copy and rename the package to .zip and check inside what the package contains.

As a test you could upload the individual files (creating your own project)-to test if this is possible and not that something within the package is corrupt.

I was playing around this this for over an hour until I found out that the error has to do with other files located in the folder, that for some reason SDL confuses with the project itself. Once I've relocated the package into a new folder, pointed this new folder to be the folder for the project, and started the project from there - everything worked well. That was really bizarre. 

But thank you very much for the assistance! and maybe this little post will be helpful for someone else in the future...