Trouble with Network Key and Connection

I have a dell laptop with wireless capabilities and a netgear router. My laptop recently had a trojan and windows needed to be completely re-installed. I am able to get on any unsecured network, but the network I installed myself (with security and the best connection) won't work. It appears that it's rejecting my security key, and I haven't been able to figure out how to remedy that, or to establish a new network with a new password to just start fresh. Any suggestions?

What are the settings on the wireless network? WPA, WPA2? If it's not accepting the connection the key may have been fat fingered?

I'm sure you may have already reviewed these items but I'm just trying to get more information and maybe help you figure it out.

it was set up as WPA. i've typed it in before the re-boot and have never had trouble; but it is not being accepted after multiple tries on both my comptuer and my wireless enabled cell phone.

You stated on your Dell it had be completely re-installed. I'm assuming the drivers have all been updated to the latest versions? If the settings work with no encryption but fail once encryption is presented, then it could be due to some of the following reasons -

1. The NIC card does not support the level of authentication/encryption being used (WPA, WPA2, TKIP, or AES). A driver upgrade on your NIC should resolve this.

2. The settings on the wireless router do not match those on the PC. (Network Key, Network Authentication, Data Encryption.)

We know the settings work with no authentication and encryption. So lets try to 'bump' it up. Try setting up your settings using WEP. I know it's not the safest way but lets gradually increase the security settings so that we can find out which one of your devices does not support what. If WEP works then we can move up to back up to WPA for Authentication and use AES for Data Encryption.