I cant open attachments from my email service fastmail.
I get an error from Mozilla when trying to open a pdf from my fastmail account. See screenshots. I think its a certifugate that needs to be installed but for the life of me I can't find it.
Additional System Details
- Shockwave Flash 32.0 r0
- User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:69.0) Gecko/20100101 Firefox/69.0
There is security software like Avast, Kaspersky, BitDefender and ESET that intercept secure connection certificates and send their own.
- uses an invalid security certificate SSL_ERROR_BAD_CERT_DOMAIN
- configured their website improperly
How to troubleshoot the error code "SEC_ERROR_UNKNOWN_ISSUER" on secure websites https://support.mozilla.org/en-US/kb/troubleshoot-SEC_ERROR_UNKNOWN_ISSUER