Resolved Unable to access Updates page

[KendalSmithy]

Server operating system version

Ubuntu 22.04.2 LTS

Plesk version and microupdate number

Plesk Obsidian 18.0.53 Update #2, last updated on June 20, 2023 01:26 PM

The only page which I cannot access in Plesk is the Updates page. I have opened firewall port 8447 but to no avail and after a few seconds I receive this error:
(URL followed by...) PR_END_OF_FILE_ERROR
Can anyone advise me?

 

[Peter Debik]

PR_END_OF_FILE_ERROR is a message that indicates a network connectivity issue between your browser and the SSL/TLS secured website. There are a few suggestions what you could try:
1) If you use a security software such as a firewall or antivirus solution on your computer, try to disable it.
2) If your router is blocking port 8447, let it access port 8447.
3) If your datacenter firewall is blocking that port, let it access port 8447.
4) If you are using a VPN or Proxy, these might not connect 8447 to your server. Disable VPN or proxy so that your browser can connect directly.
5) Reset your browser's SSL settings.

 

[KendalSmithy]

Thanks Peter.
The problem is in my router and a quick workaround was to use WiFi Hotspot Tethering on my mobile phone.