The Norfolk and Suffolk Integrated Care Board, responsible for overseeing health services across the two counties, has been contacted for comment.
NHS England said it had contacted practices to ensure the impact on patients was minimal.
A spokesperson said: “While the majority of GP practice websites are running as normal, some practices which use Silicon Practice will be affected by the company going into administration.
“If your GP practice website is unavailable and you need help, you should contact your practice by phone or in person as usual.”
On 16 October, Schappit, the owner of Silicon Practice, filed a notice of intention to appoint administrators, external after facing financial difficulties.
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