Upgraded XG330 Appliance from 17.5.12 to 17.5.13 - Lost connection to Web console and user portal: "PR_END_OF_FILE_ERROR"

Question

Hi all, 
 
 Upgraded XG330 Appliance from 17.5.12 to 17.5.13: After that update connection neither to web console nor to user portal is possible: browser says "PR_END_OF_FILE_ERROR". 
 Firewall is up and also working... but I am unable to manage any more. 
 Any hints? 
 Update: It seems, that the certificate for the webconsole access is gone: Browser says when checking the cert: Web Site Identity - Owner (This web site does not supply ownership information). No Button "show certificate" in any browser available when opening port 4444 or 1443. The certificate is gone.

GernotMeyer · Accepted Answer

Solved it and resetted the cert via cosnole (2->4). 
 Followed this article: https://community.sophos.com/kb/en-us/133678 
 Thanks for help!

FloSupport · Answer

Hi All, 
 This issue is observed when the custom certificate used for WebAdmin and User portal access has a space character in the Certificate name. 
 This issue is tentatively scheduled to be resolved in SFOS v17.5 MR14 and v18 MR3. 
 Note: If the issue persists after attempting the workarounds below, please raise a support case and reference the ID NC-61956. 
 
 Workarounds 
 
 Re-import your client certificate with no spaces in the certificate name 
 Reset the default Certificate
 
 Reference this article to access your device via SSH: https://community.sophos.com/kb/en-us/133678 
 
 Access Sophos XG via console or SSH connection. 
 Navigate to Option 2 "System Configuration" . 
 Select Option 4 "Reset Default Web Admin Certificate" 
 Type ' Y ' to continue.