We use cookies to provide you with a better experience. If you continue to use this site, we'll assume you're happy with this. Alternatively, click here to find out how to manage these cookies

hide cookie message
2,862 Tutorials

How to fix 'URL not valid' messages

Fix hyperlink security problems

QUESTION When clicking on a hyperlink in Mozilla Firefox I often get a warning that the ‘URL is not valid and cannot be loaded’, even when I know it’s genuine. My PC runs Symantec Norton Internet Security 2010 and a-squared Anti-Malware, but I can’t find any settings to adjust to prevent this happening. Martin Perry

HELPROOM ANSWER You shouldn’t be running both Norton and A-Squared, Martin. Running two security products that provide the same function simultaneously can cause them to clash, producing random behaviour problems.

If you’re unable to uninstall A-Squared using Add/Remove Programs, you may need to boot the PC into Safe mode first.

The error message you’re receiving is likely to be caused by a Firefox browser add-on (although the Google Toolbar is often wrongly blamed). In Firefox go to Tools, Add-ons and disable all entries. If all is well after restarting the browser, enable each add-on in turn to identify the culprit.

See also: How to fix everything: the ultimate guide to fixing technology

Get free tech support 24 hours a day at PC Advisor's Helproom Forum

IDG UK Sites

Very best Black Friday 2014 tech deals UK: Latest bargains on phones, tablets, laptops and more...

IDG UK Sites

Black Friday feeding frenzy infects the UK

IDG UK Sites

VAT MOSS: Will I be affected by the EU VAT changes? Here are the facts for designers and artists

IDG UK Sites

Black Friday 2014 UK: Apple deals, Amazon deals & Black Friday tech offers