I integrate an $OEM$ folder into my ISO. After years of doing this without any problems, I suddenly have the following phenomenon: All files from the $OEM$ folder are write-protected in the installation on the virtual machine. As a result, the ISO does not work in some cases.
The crazy thing is that this is not the case when installed directly on a PC. So I thought the error was in Virtual Box, so I used VMware. Same behaviour there! Even if the VM is running on a different PC!
Do any of you, who surely work a lot with virtual machines, have an idea why this is happening?