Two questions

First question, I want to get a wireless card for my laptop for work. Will any card work with any router or must I get a specific card for their router? I have no idea what type of router they have currently.

Second question. I have a three computers at home connected via linksys wired router. One system in our bedroom, one in my daughters and one in my office. I am unable to access my office computer from my daughters room. All other connection conbinations work fine. I get the message that I am unauthorized and to check with my network advisor. I don't have a network advisor to ask!

 

Some Routers can do better with their own Brand matching card that can use some additional propriety capacities (like extra speed).

However, any 802.11g card works with any 802.11g Wireless Router using the standard mode.

As for sharing, may be this can Help.

Successful Sharing involves some general consideration in Network settings, http://www.ezlan.net/sharing.html

As well as specific adjustment of each computer according to what is allowed to be shared.

http://www.microsoft.com/technet/prodtechnol/winxppro/maintain/filesharing.mspx

http://support.microsoft.com/default.aspx?scid=kb;en-us;304040

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