I can receive but cant send in Messenger 4.7

Hi! I am running on Windows XP Pro with a linksys router. I already went into network connections and right clicked it, went to properties and made sure that the firewall was off. I also checked “connections” under tools->options and it said that “I am currently connected to .NET messenger service directly without a firewall”. I can receive files that are sent to me but when i try to send files i get the error message “cant send files, check internet connection settings and check with your network adminstrator” (not exactly but along those lines). I went to linksys and checked out their site. Not much help.

I was wondering, why and how can i fix my not being able to send files in messenger?

Secondly, this may be a stupid question, but i currently have 3 computers running on my network ranging from Win98->Win2K->Win XP. If i wanted to update to the latest firmware version from linksys, it says to “pick a product” and to “pick an operating system”. If i am on my Win XP computer i would choose my router type and Win XP as my O/S, and if i am on my Win98 O/S i would have to choose the router type and Win98 as the O/S, does it matter which computer from which i download the latest firmware? Thank you in advance for any and all help.