Hello,
I have tried to connect my computer with the ETHERNET port and not connectivity. I have tried with a wireless connection...no connectivity. I have purchased 3 wireless adapters still nothing. I do not know what to do. Please help me. (I'm on my daughter's laptop and she is wireless and connects wired and/or wireless. Please help  Did it ever work? If so, what is new or different since the last time everything worked properly (ie, new HW, new sw, virus, error, etc)? If not, please provide some background and info on the system.

Also, please look in device manager. Are there any errors?Yes it has worked...up until last week. I put avast antivirus. Sorry Alan. The only "new" is avast and SuperAntiSpyware.Then uninstall Avast and REPLACE it with a different AV. Let us know what happens.Why would avast be the problem? Ok I will uninstall it....I have no idea. But do not uninstall it without installing a different AV. Do not run your system without an AV.This doesn't make any sense. I have avast on 4 computers and they are all fine. In fact the computer that I'm on has avast. Ok let me see what the computer is doing.
.....
Just like I knew would happen..... still no connectivity...We need to eliminate anything new before we go any further. Okay, feel free to reinstall Avast. Now please check device manager for errors.I do have an error.
PCI Simple Communications Controller has a yellow ? mark on it.Make and model of your system?Intel (R) Core (TM)2 Duo CPU
E6550 2.33 Ghz

Dell Inspiron 530Go to the Dell support website, enter your service tag number, download and install the chipset driver and the pci simple communications controller driver. I'd go there myself and give you more info but I'm logging off for the evening now.Look Under Chipset & Network drivers.  Enter you Service Tag.
http://support.dell.com/support/downloads/driverslist.aspx?c=us&cs=2684&l=en&s=pub&os=WW1&osl=en&SystemID=INSP_DSKTP_D530&catid=-1&impid=-1