Hi everyone,
Whilst trying to install a Sagem broadband USB modem, the pc recognises the NEW HARDWARE, the drivers are loaded, but when the pc says "Searching for software for the new hardware", I am asked to insert Win98 cdrom as it can't find the file "ISDNUI.DLL".
Even after I have inserted the Win 98 disc, the system says it cannot find this file.
Can anyone help me please?

This file is included on the Windows 98 installation disk. It's compressed within filename: NET7.CAB. The installation should automatically find and extract the file when disk is inserted into the cd-rom drive..... if you point the installation to the Win98 folder.

You may extract the file manually by using this procedure:

1: Open Windows Explorer, navigate to the Win98 folder on the drive containing the Win 98 installation disk.
2: Locate file: NET7.CAB, right click it, left click VIEW.
3: Find needed file in the list (isdnui.dll), right click it, left click EXTRACT.
4: Choose destination folder (usually C:\Windows\System) and click OK.

Note: Please do not post in UPPER CASE. It took me longer to edit your post than it did to answer your request.
:)