Were My Tasks migrated from another version?  If you add a new task to My Tasks, does the same thing happen?  If could be the ID's changed, and your My Tasks links are corrupted.

I have heard when this error occurs on Windows 10 PCs to try using the UNC path in the 2 places in the shortcut (the Target and Start in) instead of using a mapped drive. Also that if you use 3rd party products run from this PC that integrate to Sage via mapped drive to change those to UNC as well.

Thanks, I'll try this and report back. Unfortunately, none of the other suggestions have worked for me, though I am waiting on feedback about the My Tasks part. That may not be the case now that I've gotten clarification from the user--she seems to get the error no matter what shortcut she uses.

Make sure the user has read / write permissions to the entire MAS90 folder (and all contents).

Yeah, looks like the security group has the appropriate perms--actually maybe a bit too much access now that I'm looking at it.

Well, I touched base with the user today and this seems to have addressed the issue. Normally it would've already cropped up by now. So, at least for now, I'll verify this as the answer for my particular issue.

Thanks again