Web users attempting to trace their ancestors remained disappointed today when the public records office failed in its bid to get the massively popular 1901 online census back up and running within a week.

BT, the internet service provider responsible for hosting the census website, asked the PRO to pull the site days after it was launched, when more than seven million people tried to access the site at the same time. The site was designed to handle only 1.2m visitors over the course of a day.

The PRO said it hoped to have the site operating again early this week, ideally today. But the site's address, census.pro.gov.uk, continued to take users to an apology page this afternoon, or the page failed to load at all - indicating high numbers of users accessing the apology.

Ongoing problems accessing the site have been a huge embarrassment for the PRO, which launched the census website among huge publicity two weeks ago. The website offers access, for the first time, to the details of more than 32m Edwardians. Genealogy is now second only to pornography in popularity on the internet.

The site has been suspended since last Tuesday, while the PRO and its technical advisors, Quinetiq, formerly part of the Ministry of Defence, attempt to increase its capacity.

Staff on the website's helpline were today unable to say when the site would be operating again.