Cant move emails to pst files

We are having this issue in our company as well.  We were forced into using the new Outlook due to using a Telus email, but we had been using a .pst file for many years.  Since the .pst is only partially supported in the new Outlook, it now acts as 'storage' and we have been moving emails we need to file into the .pst.  A few days ago they started bouncing back out, even though we get a pop up asking if we want to move the email.  Very frustrating and we hope that Microsoft fixes this, and all the issues for those of us that have been using .pst files in Outlook for years!