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It could be a USB cable problem and it's easy to test with another cable if you have one. If you need to buy another cable make sure that it's rated as a "data transfer" cable. Some of the lesser, "budget" USB cables may work OK for charging purposes but not so well, or at all, for data transfer.
Have you downloaded any Windows Updates recently?
09/26/2023: New firmware updates are available.
08/18/2023: Canon EOS R5 C training series is released.
07/31/2023: New firmware updates are available.
05/31/2023: New firmware updates are available.
05/18/2023: New firmware updates are available.
03/30/2023: New firmware updates are available.