London’s Metropolitan Police has missed its deadline to dump Windows XP, with tens of thousands of copper still running the risky OS.

The force, on the front line against terrorist threats and criminals in the capital city, is running Windows XP on around 27,000 PCs.

At last count, in May 2015, the Met had a total of 35,640 PCs, with 34,920 of them running XP. Policemen set themselves a deadline of March 2016 to finish migrating to Windows 8.1.

London Mayor Sadiq Khan, however, has apparently now revealed that just 8,000 of the force’s PCs have moved to Windows 8.1 since last September. The target is for another 6,000 by the end of September 2016.

Khan provided the update in response to a question from Conservative Greater London Assembly member Andrew Boff.

The Labour mayor told Boff in a written statement:

“The MPS [Metropolitan Police Service] are developing further plans to address the outstanding XP desktops including reducing the overall number and disposing of equipment that cannot support Windows 8.1.”

Boff expressed concern over the fact data and information belonging to, and about, Londoners is being processed by PCs running the ancient OS.

Microsoft stopped delivering security updates and bug fixes for Windows XP in April 2014. That means Windows XP users still running the 15-year-old operating system after that date are on their own against new forms of malware and viruses.

Only those who pay Microsoft for a special Custom Support Agreement get to enjoy continued support. The Met had paid Microsoft for a CSA back in 2014.

The Met was to move off Windows XP under its Next Generation Desktop programme, which started in January 2015 and was to be completed in March this year, according to the force’s response to a FoI request lodged by The Register in 2015.

It’s clearly missed that date.

Boff challenged the wisdom of sticking to the Windows 8.1 migration, given Microsoft has since superseded this with Windows 10. It’s a rarity for enterprises and governments to have moved from Windows XP to Windows 8.1 – if anything, organisations went to Windows 7.

Gary Schare, president of Browser management expert Browsium, who has worked with some big UK government departments, told The Register: “There were very few who went to Windows 8 as an enterprise.”

Share also reckoned the Met is not alone in continuing to employ Windows XP on such a vast scale. He reckoned on a long tail for Windows XP, with some still running on tens of thousands at workplaces across the UK.

“We’ve come across a number of large organisations often in government where there’s some big pockets of XP. Often you see a major department in a large bank that never got off XP but other departments did,” Share said.

The Metropolitan Police did not respond to Register questions by the time of writing. ®