Site Notice On Saturday, The Register suspended service by third party ad serving supplier, Falk, following security issues detailed here.

Today we have restored the service, after satisfying ourselves that this problem is fixed. Falk's statement on what went wrong is here.

Our thanks for all your emails. We appreciate the kind words and note the performance issues that many of you raise. We will be seeking to address this in coming weeks.

At a rough guess, the number of Reg readers exposed to the Bofra /IFrame exploit was in the low hundreds. We have no means of estimating how many of these were protected by firewalls or anti-virus software protection.

During the period Falk's service was compromised - between 6.10am and 12.30pm on Saturday, 11660 unique individuals using Windows and IE6 visited The Register. We haven't drilled down the different flavours of Windows, but we assume that the majority were not on Windows XP SP2 boxes. Reader with Windows XP SP2 are protected from the Bofra /IFrame exploit, along with the rest of the non-Windows world. On average readers looked at three pages a pop. So that's around 35,000 pages in which the rogue ad could have been served. According to Falk, one in 30 requests for a banner ad were redirects to the site containing the bofra worm. If this is correct around 1,170 rogue ads were served on our site.

We apologise again for exposing readers to this. We also urge readers using IE on Windows to switch browsers, at least until the iFrame exploit is patched properly.

Here is advice from McAfee on removing the Bofra worm. ®