Display Moreanything can cause a problem, specially when there is a lack of planning and preparation.
but problems can be minimized by doing right steps such as making backups (yes, more than one).
at least archive and image, preferably also WoV project and KRCDiag and all options from D:\
some info is redundant among those backups but depending on what you are dealing with, each can have some advantages and if one of them is corrupt somehow, you will have options out of the situation. the thing is you will not know for sure if some backup is good until you try it.
also if the image is from another robot, i would advise to not use it on this one. options, configuration etc could be different and you don't want same SID on two robots.
note, KSS upgrade will try to keep all programs and settings as they are.
KSS new install will wipe them all out.
i would make backups and then upgrade this robot with newer KSS. some upgrades are fussy and i have seen robot not moving to new KSS without some "convincing". in that case rename D:\KRC_Relase to D:\KRC_Release_old. then place D:\KRC_Release from the image you have (you can extract this folder using 7zip).
this way upgrade should work every time even on fussy ones...
Okay, I have an image that was passed on to me by a kuka technician, it is meant to be factory. To solve this problem, I will make a current image of the robot and also a backup, then I will pass the image 8.3.39 from the factory and restore the backup, I believe that this way the problem will be solved, if it does not happen, I have the previous image as a backup .