YESTERDAY, all their troubles seemed so far away. But now it looks as if they're here to stay.

The BBC has admitted that it has lost vital footage of thousands of performances by bands from the golden age of pop music in the 1960s.

Of the 3500 performances shown on Top of the Pops in the 1960s, a mere 55 remain in the corporation's archive. Footage of live performances by The Beatles, Rolling Stones, Kinks, Bob Dylan and other artists has been lost forever.

The admission comes after the BBC's nostalgic music show, Top of The Pops 2, broadcast a special on the Beatles last month which included various clips of the band from early performances.

The BBC was then asked, in letters to the latest edition of its in-house magazine, Ariel, why the show could not show performances of early Beatles successes such as She Loves You and Please Please Me. The answer in response was simple: the BBC had deleted them.

Mark Hagen, the producer of Top Of The Pops 2, said: ''I would have loved to use clips of The Beatles on Top of the Pops but unfortunately none of them survives in our archive.

''From around 3500 1960s performances on the weekly show, the BBC now retains 55, by no means the 55 you would choose to keep now.''

The BBC is trying to piece together the archival history of Top of the Pops to find out what happened to the missing shows. Many programmes from the past no longer exist because there used to be a policy of recording over old film to save money, before it was possible to transfer footage on to video or other formats.

Last night, a spokeswoman for the BBC Archives in London said that 40 years ago many at the station did not realise the ''historical and social value'' of live broadcasts.

Indeed, a number of programmes were broadcast live and not recorded on film at all.

She said: ''This issue is not a new one. We have one of the world's largest archives of sound and film but yes, some of it is not all there.

''There are several reasons but in the 1960s tape was also expensive and bulky to store and programmes were often simply copied over, while only excerpts or scraps of shows have been kept.

''Different procedures are in place these days and we are also working very hard to digitise our files to combat the deterioration of film.''

It is not the first time the BBC has admitted to losing hours of past shows.

Three year's ago, the corporation even had to make an appeal to viewers, urging them to look through pre-1980 television or radio shows taped at home during the original broadcast to add to their files.

Episodes of The Likely Lads are lost, as are the first six episodes of the gentle Scottish comedy Para Handy.

A one-off appearances by The Beatles and The Rolling Stones on Juke Box Jury is lost as are nearly half of Hancock's Half Hours recorded for radio.

The Beatles' only live appearance on Top of the Pops, on June 16, 1966, to perform Paperback Writer and Rain, is also missing.

Obsessive fans of the creaky BBC science fiction show Dr Who were also horrified to find that of the hundreds of episodes made, some 109 episodes have also been lost.

Comedies that have been wiped include episodes of Dad's Army, Till Death Us Do Part and The Likely Lads.

With the footage of The Beatles in particular, the BBC cannot show what footage they have often, because almost everything the band ever performed is controlled by Apple, The Beatles' company, which owns the copyright.

Hagen, writing in Ariel, added: ''Yes, there is a copyright problem.

''Apple owns and/or controls virtually every piece of film in which the Fab Four perform and so what we can show is entirely dependent on what they will clear for broadcast.''