I recently upgraded to Windows 7 from Vista (Now Running Win7 Ultimate x64)
I tried reinstalling guild wars and it gets past those first files fine(The smaller one before the main update I presume the file list) But when downloading the main part of the game it gets very slow and downloads data in bursts around usually under 100kB's each time it gets data.
When I ran Vista Home Premium x64 it worked fine and now it just doesn't.
I have tried the following to solve my issue:
Opening ports TCP 6114 & 80 over windows Firewall
Running as admin
Running in compatibility mode with Vista SP1/XP
Uninstalling and then reinstallng
However none of that has done anything.
I can only assume its a problem with 7 but as far as I know everyone else has no problems running it.
you may need to put it on your exceptions list in your AV program (also windows defender) - it should work, I installed a win 7 upgrade over vista and it worked fine for me.