Got it!
And did a more elaborate tutorial.
1- Search for Fiddler on google and download it
2- Open Fiddler
3- Go to Tools > Fiddler Options > Connections > mark "Allow remote computer to connect" and OK.
4- Restart Fiddler
5- Press "Control + R" to open a file with a Notepad in Fiddler.
6- Press "Control + F" to make a search and paste this:
OnBeforeRequest(oSession: Session) {
7- Click on "Search Next"
8- At the next line, paste this code:
if(oSession.uriContains("RM-821_eu_euro1_425"))
{
oSession.url = oSession.url.Replace("RM-821_eu_euro1_425","RM-877_nam_att_205");
}
9- Now you have to change both "RM-821_eu_euro1_425" to Manufacturer Name from your Lumia. You will find it on Extra+Infos on your Lumia.
10- Save the Notepad file and close
11- Now pickup your phone and forget about your PC. Click on WiFi settings, connect with the same WiFi you are connected on your PC.
12- Still in your phone and WiFi options, click on your WiFi, Activate proxy and put your PC IP Address on Server field. On port field, put 8888.
13- Now you have to search for QR Codes below