1) Open the 'Dial-Up Networking' folder in 'My Computer'.

2) Edit the DUN you wish to 'optimize' by selecting it and choosing 'Properties' as shown

3) Select 'Server Types' tab and setup the 'Advanced options' and 'Allowed network protocols' as shown below. Do not tick any other boxes, setup exactly as shown below.

4) Select 'Configure' from the 'General' tab.

5) Select 'Maximum speed' list and select either '115200' or if possible '230400'. Should you have any problems at 230400 reset it back to 115200.

6) Select 'Connection' tab and make sure it is setup as shown - Data bits 8, Parity None and Stop bits 1. Then select 'Port Settings'.

7) Make sure that 'Use FIFO buffers' is ticked and then move 'Receive Buffer' and 'Transmit Buffer' to High. If you experience problems when connecting or online select the 'Defaults' option. Select 'Okay' and exit DUN setup.

8) Dial the ISP using the optimized DUN you have just created. Check that in 'Status/Details' either 'Microsoft compression' or 'Stac compression' is shown under the 'Protocols' entry. If it is not then check that the ISP is in the 'Supports Compression' list in the 'Choosing an Internet Service Provider' page.