How to create a Dial up on windows Vista for all types of USB modem.

click on "start" and go to "control panel" as you see in the image above.

switch the view to "classic view" open "Network and sharing center" like you see in the image above.

on the left of the screen click on "setup a connection or network".

you will get a list of options. select "connect to the internet" and then click next as you see in the image above.

here you will see some of the connections that already exists on your computer. select the option "No, create a new connection" and click next.

from the list of options select "Dial-up".

in this e.g. we are selecting the "Nokia GSM Phone USB Modem". You can choose the modem you would like to use to connect to the internet.
enter the dialup number as *99# unless specified by your internet service provider.
Note: for Sony ericsson handsets the dialup number is *99***n# where "n" is a number. e.g. 1, 2 etc.
leave the username and password blank unless specified by your internet service provider.
once done click on "connect".

you are ready to use the internet connection once you see this screen above.
to access the connection you have just created you can click on the start button, go to "connect to" and click on the connection you just created.