Freeserve claims its networks have become log-jammed by a flood of new subscribers from failed unmetered internet service providers (ISPs).
In a newsletter to customers, Freeserve said the withdrawal of unmetered access packages by other ISPs - including Lineone and Callnet - has lead to an increase in Freeserve subscriber sign-up.
It said this was the reason why many users, especially in the North of England, have been experiencing problems connecting to Freeserve. Users have complained of difficulties logging on and the frequent need to make multiple attempts to connect to the service. Other users have experienced decreased download speeds.
A Freeserve spokesman said: "We're proud to be one of the few ISPs who provide unmetered services. Others have suffered from the strains of partnerships and miscalculated demand, but there is no question of us pulling our service. We have had an increase in users to our services and have been busier in the last few months.
The company said it has been working with its telco partner Energis to improve bandwidth problems, and expects the service to return to its "normal standards" by the middle of September.
During August, ISP LineOne announced its intention to abandon its 0800 service with telco Quip at the end of September, after admitting it can no longer support the economics of providing free access. Cable operator NTL has admitted that it has more than 150,000 customers stuck in a queue waiting to sign up to its own unmetered service.
Freeserve said it currently has around 140,000 unmetered customers, roughly halved between its Unlimited and Off-Peak packages. Including its metered service, it has around two million customers.
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