First of all, before I tested around, I took screenshots of the 100 scans when scrolling through them in the Microsoft Lens app. This takes some time and you will not need to do that when you follow steps 1. and 2., but if you are unsure and do not face the same thing, you should take the time to know at least which scans you lost if you lose them.
- Open the “Media” (NOT THE “My Scans”!!)
In the Microsoft Lens app, tap the bottom left icon that looks like a little framed picture of a hill and the sun at the top right of the hill to enter the “Media” overview inside the Microsoft Lens app:
Mind again: this must enter the “Media”, NOT THE “My Scans” that you reach with the “house” button on the top left; do not try that house, nor try the top right menu for “My Scans”, since you will lose your pictures as soon as you agree to discard them. Do not ask me why they programmed it like this, I even thought as a beginner after having much of the same upload problem as here that discarding would perhaps be right in the sense of getting rid of the scans and by the same time uploading them. I was wrong in hoping that and lost all scans.
Now in the “Media”, you can view all your 100 scanned images numbered from 1 to 100. If you scroll down to number 1, you see that the other pictures that come below without a number stem from your media folder on your iPhone.
- Then change the order of photos in Media by a tiny bit:
In the “Media” section, uncheck one or more photos, then recheck them.
*(I even also changed photo 100 to 99 and photo 99 to 100 and changed that back again, but I doubt that this triggers the main fix; drop a remark if you did not need it, then I drop this.)
After this “trick” of reordering without a change, the photo list was refreshed, I saw one or two new scans that had been hidden before, at least I could not find them in my saved screenshots of all 100 scans that I took in case I would lose all of them in the Lens app. And with this refreshed photo list at hand, I could press on “Done” to reach the menu for the upload which should look like this (the screenshot is taken from the Microsoft Lens für iOS – Microsoft Support):
Thus, once the photos are reordered and the new “last” photo is visible, press “Done” again. This allowed the app to move forward and show the upload menu to OneDrive without hanging.