Avast online security extension error software#
You could try reinstalling it, which might trigger the software into placing its certificates into the Firefox trust store again. Third-party antivirus software can interfere with Firefox's secure connections.
Avast online security extension error code#
In particular, the error code MOZILLA_PKIX_ERROR_MITM_DETECTED indicates that Firefox detected connection interception. The most common causes are security software scanning encrypted connections, or malware listening in and replacing legitimate website certificates with their own. If you get this problem on multiple unrelated HTTPS-sites, it indicates that something on your system or network is intercepting your connection and injecting certificates in a way that is not trusted by Firefox. The error occurs on multiple secure sites
If you click the Advanced button on a "Warning: Potential Security Risk Ahead" error page and you see the error code SEC_ERROR_UNKNOWN_ISSUER or MOZILLA_PKIX_ERROR_MITM_DETECTED, it means that the provided certificate was issued by a certificate authority that is not known by Firefox and, therefore, cannot be trusted by default.
3 The error occurs on one particular site only.2.3 Monitoring/filtering in corporate networks.2.2 Family Safety settings in Windows accounts.2 The error occurs on multiple secure sites.