Unable to update Plesk: Error in cURL request: error setting certificate verify locations:

Symptoms

Unable to update Plesk components:

C:Program Files (x86)Pleskbinextension.exe --upgrade-url https://ext.plesk.com/packages/bebc4866-d171-45fb-91a6-4b139b8c9a1b-panel-migrator/download?2.17.1-723 failed with error 1(0x00000001). Output:
STDERR:Error in cURL request: error setting certificate verify locations:
CAfile: C:Program Files (x86)Pleskadminconfcacert.pem
CApath: none

Cause

PHP cURL is using an outdated set of root certificates to verify server certificates; the certificate file is missing in the curl.cainfo directory.

Resolution

1. Connect to the server via RDP.

2. Open %plesk_dir%adminconfpanel.ini file (create it if it doesn't exist) and add the below directive to it.

   [php]
   curlCertificatesUrl="http://curl.haxx.se/ca/cacert.pem"

3. Download the cacert.pem file from the main curl website http://curl.haxx.se/ca/cacert.pem.

4. Place the downloaded cacert.pem file into the directory set as curl.cainfo in %plesk_dir%adminconfphp.ini.