Hi,
I have been using teams for quite some weeks now. I have created channels as a Owner and other member of the teams only as Members - Who can edit etc. But will not be able to delete the file. However recently I had a problem with my outlook account so was forced to do a online repair of my Microsoft Office. Since then when I open those excel files with my Excel desktop application, which are there in my channels I am able to open the files Only in "READ ONLY" option. Following is the screen shot for your reference.
However when I open the same file in Excel Online it works absolutely fine.
Please give a solution for the problem.