- Plesk for Windows
Note: This article has the reference to the issue with the fix available:
Server backup finishes with warnings:
CONFIG_TEXT: [WARNING]: [e4dfb1b5-edcb-487b-bd12-d91e1a836b1f]: Unable to check existence of the file C:\Program Files (x86)\Plesk\var\modules\letsencrypt\etc\live\example.com\cert.pem. The file will not be archived. [:8449200]
Let's encrypt certificate is installed on the affected domain.
This is Plesk bug with ID PPPM-6126 which is fixed in Plesk Onyx 17.5 Update 24.
Upgrade to the latest Plesk version via Plesk installer.