A study by the Department for Culture, Media and Sport of 400 homes in Bolton found that while more than two-thirds of triallists were able to install the equipment themselves or with the help of friends or family, most still experienced problems after installation.
The study found 74% were still reporting problems with their equipment four weeks after digital TV was installed.
A month later this figure dropped to 20%, and over the long term almost all (98%) were happy with the change.
The results of the study will be closely watched by the BBC, which as part of its licence fee bid intends to set aside an as-yet unspecified amount to fund so-called 'targeted help' for the elderly and disabled when digital switchover begins in 2008.
Broadcasting minister Shaun Woodward, appointed two weeks ago, said the trial had highlighted the need for easy-to-use equipment for the elderly and vulnerable, and called on manufacturers to develop suitable products.