Hello,
Please create a separate thread for each different question, as mixing multiple topics in one post can cause confusion.
Regarding your question, “Is it possible to receive a credit note for an MS subscription?”, please refer to the response provided by Q&A Assist.
Unfortunately, it is unlikely that Microsoft will cover repair costs for a PC even if the issue occurred after a Windows Update. This is because users agree to the “Microsoft Software License Terms” during the initial Windows setup.
Press Windows + R, type “winver”, and check the “Microsoft Software License Terms”.
Please review sections 6 and 9 onward.