Government departments using Microsoft operating systems and browsers should move to the latest software versions, according to CESG, a branch of intelligence agency GCHQ.
Departments are free to choose their own operating systems, CESG told ZDNet UK on Friday.
"CESG has encouraged government departments already using a Microsoft desktop or server operating system to use the most recent version of the operating system," said a CESG spokesperson. "This is not the same as encouraging departments to move from another vendor's operating system onto Windows 7."
CESG said it had issued guidance to the government through a CESG Information Assurance Notice.
Government departments using Microsoft's Internet Explorer (IE) web browser should also migrate to the latest version, IE9, CESG said.
"For those government departments already using Internet Explorer, CESG's advice is clear; wherever possible, they should upgrade to the latest, fully patched version of Internet Explorer," said the spokesperson. "If such an upgrade were to have an adverse affect on key operational systems, then it is for the department concerned to carry out appropriate risk management."
The UK government has resisted moving systems onto more recent versions of Microsoft software. In July the government said that it was "more cost effective" to continue to use IE6 across government.