swapped from xp to 7 and problems

not sure if this is a windows 7 or 2820vn problem.

but ever since swapping to windows 7 from xp, nothing works well any more. i cant log in to bad company 2 and when i log in to sc2 i get micro disconnections (achievements enabled/disabled spam)

if i disable the windows 7 firewall i cant even connect to steam!

if i put my computer in dmz mode i cant connect either.

in xp everything just worked no problems.

any ideas?

Have you hard-coded the IP and DNS addys in the PC, or let the router decide them?

Had you set the MTU in the router for XP specifically? Vista & Win 7 work out their own MTU.

ips are assigned by dhcp

i havent tweaked the mtu on either the router or network card

In reply to a post by XRaySpeX:

Had you set the MTU in the router for XP specifically? Vista & Win 7 work out their own MTU.

actually what should the mtu in the router be set ot?

Mine is set to 1500 and no problems

Full install or upgrade?

i always do full reinstalls

Genuine windows CD (retail) or downloaded and burnt to cd?

I burnt a windows cd myself , direct download from microsoft and had nothing but issues everytime I used that CD. Must have burnt badly