Sheffield-based ISP PlusNet claims ISDN users are still under the impression that they have to pay through the nose to upgrade to broadband.
Earlier this year BT introduced a scheme that enabled ISDN users to upgrade to ADSL for less than £30.
If for any technical reason the conversion fails, BT will convert the line back to the original ISDN service at no cost to the end user.
Punters are charged £27.99 (inc VAT) only after they've successfully moved to ADSL from ISDN.
However, a spokesman for PlusNet said of this upgrade path: "The message is still not getting through".
Earlier this month Nildram announced its ISDN migration path to ADSL. ®
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