Avast 5 Internet security blocks network access

I just installed (upgrade from Pro 4.8) Avast Internet security on an Win XP computer SP3 and now I do not have access to my server shares or to the Internet. When I click to open a share I get a message saying that the path to the server is bad. I remove Avast and I get my shares and Internet connectivity back. I did not have any problems with Pro 4.8, nor I have any problems with 5 on Vista. I Have about 20 PC’s more to go, some XP, some Vista, and we already purchased all 2 year licenses (we are a Avast shop), but this problem with XP have me thinking over. Our 4.8 license is almos expired. What do I have to do?

Thanks,

Carlos


Hopefully, someone will be able to help you soon.