Q: Getting this error after I installed iTunes on my computer.

Hello there, FiremanNAFD15.

The following Knowledge Base articles provide some great troubleshooting steps for issues with connecting to the iTunes Store.

Can't connect to the iTunes Store

http://support.apple.com/kb/TS1368

Additionally, this article provides more info for the particularly error you mentioned:

iTunes: Advanced iTunes Store troubleshooting

http://support.apple.com/kb/TS3297

"Error 3000" through "3999"

 

Alerts with codes in the 3000 range generally mean that iTunes cannot contact the gs.apple.com server on ports 80 or 443. This may be because out-of-date or incorrectly configured security or firewall software is interfering, or due to your Internet proxy settings. If you are using a proxy, try removing the proxy settings, or using a known-good network. If that does not resolve the issue, follow iTunes for Windows: Troubleshooting security software issues.

Thanks for reaching out to Apple Support Communities.

Cheers,
Pedro.