Seit ein paar Tagen tauchen bei mir im Error Log Meldungen mit dem Referrer “” auf. An sich nichts ungewöhnliches. Nur versucht der Referrer immer “favicon.ico” am Query String anzuhängen und nicht im Hauptverzeichnis des URI bzw. der Domain zu suchen:


Tippe mal auf ein verunglücktes IE-Addon. Oder sogar der IE selbst?

Seems like its caused by the “PC Tools Browser Guard Toolbar”: Technet, Bug Report

3 replies on “”

Hi there,

We noticed the same problem on our website.
Started early Feb 2014.
favicon.ico has been frequently added to the end of random (?) urls causing errors 500.
The user-agent seems to be always IE11 :
Mozilla/5.0 (Windows NT 6.1; WOW64; Trident/7.0; rv:11.0) like Gecko

Very few people to nobody seems to complain about it yet on the internet.
The source of the problem remains a mystery for us.
Hope someone will read this blog and give us a clue.


thanks for your response, so i’m not alone with this mystery ;-). A colleage mentioned that there is a firefox chrome extension called ie-tab, maybe thats the source.

the same issue, we have checked our logs and IE11 shows the problem.
We see the problem in february 2014 as well :(

everyone has same referer, same request, same browser (IE11)…

optionName=Searchingfavicon.ico HTTP/1.1″ 200 3618 “” “Mozilla/5.0 (Windows NT 6.1; WOW64; Trident/7.0; rv:11.0) like Gecko”

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.