Windows 7 - problems with making a homegroup

hi i am trying to make a homegroup on my desktop pc so i can share documents with my 3 other laptops but i have a problem:

so first i made a homegroup on my desktop and that works but then i start up my asus laptop and i go to control panel and hen to network and there to homegroup.
so my laptop finds my homegroup i made on my desktop and asks for a password.
i enter the password and then i wait for about 2mins and then it says that it is not possible to make a homegroup on this computer,i aready tried windows problemsolver but that doesnt work neither

can somebody please help me?
and i dont know if it is important but my desktop is not connected wireless but through an internet cable to my router.could this be a problem?

Do you get an error that IPv6 is not enabled ?

no it only says/not possible to make a homegroup on this computer




and i am not sure if this is important but my firewall is from avast! internet security

It does not matter that computers are wired or wireless to join a homegroup, so we can rule that out. It is unlikely the firewall would cause you to not be able to join but I am always wary of firewalls and usually in cases like this I disable them temporarily (normally you can do this for 5mins) to test if this has any effect. If you are absolutely certain you are using the corrrect password you used when creating the homegroup you will need to look at your router and make sure everything is correct and that in network view under my computer, all your PC can "see" each other. Something like below....
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