Windows 10 reached EOS (end of support) on October 14, 2025. If you are on Windows 10, see this article.

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
Solved Archived

URL is not valid when I start private browsing.

Slick20

Every time I start a private browsing session, the error message: "This URL is not valid and cannot be loaded" pops up.

I've tried disabling all add-ons and starting in safe mode, but that didn't help at all. Any solutions?

Every time I start a private browsing session, the error message: "This URL is not valid and cannot be loaded" pops up. I've tried disabling all add-ons and starting in safe mode, but that didn't help at all. Any solutions?
Read this answer in context

Chosen Solution

This thread seems to have the solution: https://support.mozilla.org/en-US/que.../906369

All Replies (5)

Does typing "about:privatebrowsing" (without the quotes) into your URL bar produce the same result?

Yeah, it does.

Chosen Solution

This thread seems to have the solution: https://support.mozilla.org/en-US/que.../906369

Say, that helped a lot. Thanks.

Had the same problem, found out that the computer date was 10 years out of whack. Instead 2012 I went to Control Panel > Date & Time Properties and found out it was 2002. Corrected the discrepancy and cured the 'URL IS NOT VALID' problem. You can also change your date and time by hitting the F2 key upon start up and 'ENTER SETUP' to change you date and time. Worked for me!