Firefox - The error "secure connection failed" SEC_ERROR_OCSP_INVALID_SIGNING_CERT appears when connecting to Power Apps

If the error message "Secure Connection Failed, Error code: SEC_ERROR_OCSP_INVALID_SIGNING_CERT" appears when attempting to use Power Apps with Firefox, here's how to diagnose and to fix the error.

An unexpected problem that I encountered today was the following error when I attempted to use Power Apps with Firefox:

An error occurred during a connection to Invalid OCSP signing certificate in OCSP response.


The page you are trying to view cannot be shown because the authenticity of the received data could not be verified.

The error message refers to OCSP (Online Certificate Status Protocol). This is the protocol that web browsers use to retrieve the revocation status of a certificate. The error message here suggests that the HTTPS certificate for isn't valid.

I carried out a quick online search, which suggested a fix for the problem by disabling OCSP through the about:config settings area in Firefox. This is not an ideal solution as it reduces the security of the browser.

How to diagnose connection problems further

With all Power Apps problems that are related to connectivity and authentication, the first thing to try is to use a different browser. Alternatively, we can clear cookies/browsing history, or try the in-private/incognito modes of the browser.

I tried again with Microsoft Edge and the cause of the problem became very clear - the time on the computer was incorrect.

Your clock is behind Can't establish a private connection to because your computer's date and time (Friday, 18 February 2022 at 07:07:48) are incorrect.

Following a series of power outages that were caused by severe storms in the UK, the computer I was using had lost its time setting, and was several days behind. Once I corrected the time, I was able to use Power Apps without any further problems.


This post highlights how trying a different browser is always a good step when diagnosing connectivity issues. If we receive the SEC_ERROR_OCSP_INVALID_SIGNING_CERT error in Firefox, a likely cause is an incorrect time on the device, and correcting time should resolve the problem