The news comes as the leader of one of Britain's biggest unions last night urged workers not to be "bullied' into working long hours for little pay over the millennium.
Microsoft, whose working conditions led to employees being dubbed Microserfs, has taken the step amid fears of widespread breakdown in information technology systems that are unable to handle the changeover from 1999 to 2000.
The corporation has told 250 employees at Wokingham in the Thames Valley that enough people, including executives, must be on hand during the four-day break to deal with customers who have "mission critical" problems.
The firm has said that the majority of software being used by corporate clients is Year-2000 compliant, but it is taking no chances. A spokesman said: "We want to minimise disruption for our employees as much as possible, but we have to be ready for every contingency."
Meanwhile, John Edmonds, the general secretary of the GMB union said that staff in catering and the leisure services industry could fall prey to "Scrooge bosses" seeking to cash in on the celebrations.
Croupiers, pit bosses and workers at the Stanley Casino in Liverpool said they were being forced to work on Christmas Day without extra pay in exchange for the night off on Millennium Eve. They have now claimed victory after the intervention of the Bishop of Liverpool, the Right Reverend James Jones.
Mr Edmonds said he was concerned that employers may seek to reap "once in a lifetime profits". "All the talk has been of employees demanding large salary hikes for work over millennium holiday period," he said.
"Yet there are thousands of workers who would rather spend this special time with their family and friends but face being press-ganged into working excessive hours for little or no extra pay by unscrupulous bosses looking to cash in on the celebrations.
"It must not be hijacked by a small handful of millennium misers who see the birth of a new millennium as nothing more than a national lottery of Old Father Time."Reuse content