So your third laptop which runs Vista cannot connect to the Printer and Dell machine?
There are some reasons for that.
First check whether you have access to the Dell machine (whether you can reach it)
Open a command prompt and do a ping to verify the connectivity.
(The ip address should be the one of your dell machine.
You can find it by running ipconfig in a command prompt on Dell machine.)
1. If you cannot reach it you have to check the network utility (wifi or any other method you use). Make sure that it function properly.
2. ping the router using router's ip address. If ping works you can reach up to their. So from there you can check the Lynksys management console to know why it blocks the machine entering the wlan. May be a addressing issue or authentication issue. If you cannot reach it however it might have problems with the connection as well.
Make sure that you allow connections to the wlan on Toshiba Vista laptop if you use a antivirus solution with a firewall or any other firewall.
If you can reach the machine (or even if you cannot reach) you must check whether you have access to the workgroup (you have to join if you are not in the workgroup which you use) and you must enable file and print sharing. If you run the windows firewall that would block you in as well.
Its better if you can check whether the print spooling service runs.
Start -> Run
Type in services.msc
Check and enable the service.
If you can reach the Dell using a ping:
Check whether the dell machine can access the laptop. Use my network places. It will ask you for the credentials. Provide them.
If any error occurred try detecting the network. Add the machine properly to the workgroup. Enable access to the machines via file and print sharing in windows firewall. (go to the firewall go to Exceptions tab and select the File and Print sharing)
Check this Microsoft resource
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