I'm getting and error System(5) when trying to update to v. 7.8.820 on WIndows 10

Hi,
My update fails and 1password rolls back to pevious version. Here is the last line of my error log:
[2021-10-05 10:35:36.739286 -04:00] ERROR [opw_starter::transaction] opw-starter\src\transaction.rs:127: Failed to rename existing app folder: opw-base\src\error.rs:281 permission denied (error code 5: Access is denied.)

I tried closing the browsers and adding 1Password to the whitelist of my antivirus, to no avail.
Can anyone help me with this issue?
Thanks,
Peter

1Password Version: 7.7.819
Extension Version: 2.1.1
OS Version: Windows 10 Home v. 21H1
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