We're calling on all EU-based Mozillians with iOS or iPadOS devices to help us monitor Apple’s new browser choice screens. Join the effort to hold Big Tech to account!

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

Secure connection failed for months

  • 3 replies
  • 3 have this problem
  • 2 views
  • Last reply by Stans

more options

I have been getting this message since January and am starting to be concerned

Secure connection failed start.thunderbird.net uses an invalid security certificate. The certificate is not trusted because the issuer certificate has expired. Error code: <a id="errorCode" title="SEC_ERROR_EXPIRED_ISSUER_CERTIFICATE">SEC_ERROR_EXPIRED_ISSUER_CERTIFICATE</a>

  This could be a problem with the server's configuration, or it could be someone trying to impersonate the server.
  If you have connected to this server successfully in the past, the error may be temporary, and you can try again later.

Or you can add an exception… When I click on add an exception nothing happens. I tried closing Thunderbird, deleting my cert8.db file and restarting Thunderbird - no change - same message. I am running Windows 10, Thunderbird version 45.8.0

Help, please ! Thanks, Sarah

I have been getting this message since January and am starting to be concerned Secure connection failed start.thunderbird.net uses an invalid security certificate. The certificate is not trusted because the issuer certificate has expired. Error code: <a id="errorCode" title="SEC_ERROR_EXPIRED_ISSUER_CERTIFICATE">SEC_ERROR_EXPIRED_ISSUER_CERTIFICATE</a> This could be a problem with the server's configuration, or it could be someone trying to impersonate the server. If you have connected to this server successfully in the past, the error may be temporary, and you can try again later. Or you can add an exception… When I click on add an exception nothing happens. I tried closing Thunderbird, deleting my cert8.db file and restarting Thunderbird - no change - same message. I am running Windows 10, Thunderbird version 45.8.0 Help, please ! Thanks, Sarah

Chosen solution

The latest and supported version of Thunderbird as at today is 91.10.0. Thunderbird v91 was released in August 2021 and will be officially supported for one year. We're very close to the next major release (v102), it's just a matter of weeks. The official download site for Thunderbird is www.thunderbird.net

Read this answer in context 👍 1

All Replies (3)

more options

Any reason why you're using Thunderbird version 45.8.0?

more options

That version was supplied as the most recent update. However - I did start to wonder and somehow found my way to a Thunderbird 60 download which seems to have solved the error message problem but flashes up a message saying it is no longer supported... What is its status ? And are there any more choices ? Thanks, Sarah

more options

Chosen Solution

The latest and supported version of Thunderbird as at today is 91.10.0. Thunderbird v91 was released in August 2021 and will be officially supported for one year. We're very close to the next major release (v102), it's just a matter of weeks. The official download site for Thunderbird is www.thunderbird.net