EDS, the Inland Revenue's IT outsourcer, has abandoned its efforts to produce downloadable online income tax self-assessment software for the current tax year.
Instead it has signed a deal with Microsoft to send out CD-Roms of its Taxsaver 2000 Lite software to thousands of taxpayers who registered for online filing.
Despite the problems, taxpayers will be able to file their completed forms online, the Revenue told Computer Weekly.
Its Internet Service for Self-Assessment site was taken down last weekend to install and test software that would allow Internet filing of returns.
"We've always had EVR [Electronic Version of the Return], but we have had technical problems with the downloadable version," a Revenue representative told Computer Weekly.
"We had to make a decision about how to proceed." The deadline for self-assessment returns is 30 September.
For the past three years the Revenue's EVR has been a floppy disc sent to taxpayers, who had to print off a paper copy of their return, sign it and send it in by post.
Earlier this year, the Revenue made great play of its plans to entice some of the UK's nine million self-assessment taxpayers towards electronic filing, and the system was originally due to go live in April.