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Troubleshooting ISDN2e | BT Business

Troubleshooting ISDN2e

How do I check a fault on my ISDN line?

Call us and we'll check it for you. Just click on Contact us on the right of this page.

When I connect to the internet I can't use the telephone – what is causing this?

You may be connecting to the internet at 128K. That would use both the ISDN channels, leaving no line free for telephone calls.

If my ISDN line goes down, how do I access my calls?

We can arrange for all of your ISDN calls to be stored on our voicemail service. You can then retrieve them remotely. Alternatively we could apply an out of service message. This would tell your caller that there's a temporary fault on your line. This replaces the default out of service tone. The advisor will discuss these options with you whenever you report a fault on your ISDN2e or ISDN30e.

My emails won't download – what should I do?

If you can still view web pages, your internet connection is working so the problem must lie elsewhere. The first thing to check is that your email program is set up correctly. Another possibility is that your ISP's email server is temporarily off-line.


What do I do if the green Service LED has gone out?

There may be a fault on the line or at the exchange. Call or chat online with us. Just click on Contact us on the right of this page.

I'm having trouble getting ISDN2e to do what I want – how can I troubleshoot this?

Check that the green Service LED is lit. If it is, check that your hardware (phone, fax, phone system or router) is compatible with ISDN2e and is properly configured. That may involve contacting your hardware supplier.

You can make up to two simultaneous calls. Check that no one else is using the line.

My computer doesn't seem to be working with ISDN2e – what should I do?

Check that the green Service LED is on. Check that your computer is correctly fitted with an ISDN PCI card or a Terminal Adapter. If you are using extension wiring, try plugging your connecting lead into one of the sockets on the ISDN2e box. If this works, your extension wiring may be faulty or set up incorrectly. Check that the configuration switches on your ISDN2e box are set correctly. If you are still having problems, consult your equipment supplier.


I am having trouble accessing a remote computer or with network/internet access.

Ensure that your application (e.g. Windows Dial-Up Networking) is configured to make digital calls. Consult your software and hardware suppliers if you are unsure about this.

Have you told your Internet Service Provider (ISP) that you require digital access? They may give you a different number to call If you're dialling a remote computer or network, make sure that it supports digital access and that your software is correctly configured.

I can connect to the internet at 64k, but not at 128k – why is this?

Check that your ISP offers access at 128k and that they know you wish to connect at this speed. Check with your equipment supplier that your equipment is capable of operating at 128k. Ensure that your equipment is properly configured.

A large number of short calls are appearing on my bill – how can I avoid this?

Your equipment may be configured incorrectly. Some computers, LAN applications and routers can be set to poll one another at regular intervals, raising a minimum call charge each time. Try setting your routers to poll less frequently.

Some email applications send emails as soon as they are written. Change the send-mail option so that emails are sent in batches. If you use email software that checks mail automatically at set intervals, either turn off this function – so that you check for new mail manually – or increase the interval between automatic checks.

A short call discount scheme is available for ISDN calls. For a quarterly fee, this reduces the minimum call charge during weekdays, with an even greater reduction during evenings and at weekends.

I need to plug an extra Terminal Adaptor (TA) into my ISDN2e line, but each time I try my PBX system fails. Why is this?

As you are using a PBX, your line is probably operating in point-to-point configuration. If so, the exchange can only address one piece of equipment. When you plug in a second, the exchange cannot address either.

If you wish to plug a Terminal Adaptor into the line, consult your PBX supplier to see if it has an interface for a TA.

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