Technical problems are being blamed for delays in launching a computer project aimed at boosting Latin in schools which do not have a specialist teacher.
But a report from a lobby group says the threat to Latin in schools is more serious after the project "stalled".
State schools and independents will abandon the subject within the next 25 years, claims Will Griffiths, director of Cambridge Schools Classics Project.
His group has developed and markets an internet Latin study system.
The new Government-funded software project, which includes films, tests, and interactive games, has been hit by technical problems.
Ministers pumped about £4.5m into developing software for courses aimed at encouraging more pupils to study Latin at secondary school.
Mr Griffiths said the scheme had been due for national roll-out after revisions were made in 2002.
"A five-month revision project has stalled. We are 39 months on and hearing that there are technical problems but it will be rolled out shortly. The aim to get Latin back in schools will fail."
He said the scheme had involved 50 schools over the past five years and trials had seen significant increases in the number of students taking Latin at GCSE.
The Cambridge Schools Classics Project, set up by Cambridge University to promote Latin and Greek studies in schools, provided the subject expertise for the software
The Times Educational Supplement reported the software was proving incompatible with the computers used in schools.
The Department for Education and Skills said: "We are rolling out a multi-media Latin course in secondary schools designed to make Latin available to schools where opportunities to learn that subject might not have been available before.
"Part one has completed the final stage of testing and part two is at an advanced stage of testing. Both will be available shortly."