ISDN - NO DIAL TONE

Hello,

I am needing some help with a dial up connection over ISDN2e. (UK based, BT ISDN line).

First we have two of these

http://www.sitecom.com/drivers_result.php?...p;productid=104

One at one site and one at another.

Both sites have 1 server each running Windows Server 2003 R2 fully patched/updated.

One site has been established for around 3 years, some probs but nothing a quick unplug/reconnect couldn’t fix.

We commissioned this new site around 6 months ago.

Line was fitted and it remained like that for months.

Now we have plugged identical modem and server in and we receive a “no dial tone”.

We have a dial up connection (over ISDN) within windows which dials a number to connect to a system.

I have checked ISDN box and Green light goes solid when modem plugged in.

I tried new modems, taking the modems to the other site (connected first time).

Took server to other site - connected first time also!

Even had BT out who tested line to death and found no faults.

I am lost with what else I can try.... any suggestions?

Thanks

Andy