No Automatic Connection To Network

I have RC 7100x64 connected (per cat cable) to a wireless router. Windows 7 created a home network. Router is perfectly fine and my 2 laptops automatically login into the internet. In the beginning my despktop also jsut was able to be online after booting up.

At some point (I did all updates, installed all my software) the PC does not connect to the internet anymore. Tehonly way to get online is to:

- open Network Center

- leftclick "Connections: local area connection" --> disable

- go to trouble shoot problems

- then it finds " the local area network adapter is disabled"

- I click " fix it" and it will work.

I attached the screens

How can I make it connect automatically (as it did before)? I set all services I could think of to " automatic" (IP Helper etc.). From researching I read that XP had a similar problem with SP3. not sure if it is related, but coudl an update be at fault?

Everything is up to date, Kasperksy keeps viruses away, I did not do one of the registry-cleaner tools.

Since it worked at first, one of my isntallations or updates must have done it. I also did some of the "service optimizations" from here bu tundid all of them to resolve my problem.

One could say I should isntall a newer built, but first I just want to use it before I buy the real deal in October. Second, it used to work with RC 7100 and going through all the trouble reinstalling is a hassle.

Everything else works well.