The problem is solved.
As reported, updates were carried out on the deploy notebook and the BIOS was also updated. After the BIOS on the other notebooks has also been updated, it works again.
Question: After each image download, a new Windows bootloader seems to be set up (Pic. 1 = Deploy notebook; Pic. 2 = after Image download) The current version 1.3.3 of Theopenem is installed.
How do you proceed if the image is only to be updated?