Ubuntu Software Center is just another program and will open up even
if not plugged into the internet - it's when you ask it to install
something that it looks on-line :-) Presumably web browsing / e-mail
is working so the internet connection really is live ? You don't make
it clear if this system is what you are currently using to access the
group.

Try running the command below and see if that fixes things, if you get
an error then the error message will be useful !!

sudo apt-get update

Well actually the software centre is an application that runs from your hard
drive. It is the software that is on the internet. The software its
contained in repositories which are websites the software centre accesses.
It could be that you don't have the particular ones in your software sources
list that you need, or that one or more are temporarily offline.

Try refreshing your list. I'm assuming your web browser and email are
working fine. Sorry I can't be more precise but I use synaptic on Kubuntu,
which its a little different.

This may sound stupid but... On one of my computers with a wifi connection, I
would sometimes get a message or it would simply stall then give an error
message.

I have found that opening my web-browser to a streaming radio station keeps the
connection flowing while I do the updates. It seems to work 80% of the time that
I had the problem.

I think it is something else, something in the browser or OS. I think the modem
is talking but the software is not working with it. Because it says 57-75% and
blinks without the Red ! in the icon. It just wont talk from the browser. Any
ideas about that?

It could have something to do with my set up as well. I don't know much about
the connection with the router in the hall. I did manage to get a list of the
IPs in it. But parts of the Ubuntu software only allow me to enter the data but
the buttons to click to finish are not active then.

when I download from the net I get a download window. In this window it
states how fast or how many bites have been downloaded. If it's not
downloading anything it still will sit there and wait for the connection
before cancelling the download.

The results you are getting are the same results one gets while
connecting to a free WiFi connection at Micky Dees. That is unless you
start the browser first and accept the TOS AT&T requires for you to use
the free service.

So the answer is no. Synaptics will give the connection time to respond.
This can be many minutes before it tells you about the connection
problem. Before you start updating check with the browser for a
connection that works, then start your update when you see all is
working. For the record, Your WiFi hardware and the router may have made
the connection and be communicating but if a router firewall or fee page
keeps the data from making it to your computer downloads won't happen.
Sometimes resetting the router helps with this problem. Because
hardwires don't have the same security checks they typically just work.
This too can have problems if there is a software issue. The answer is
the same, restart the router.

A story. I was at a rest stop in NM that advertised free wifi. I could
not connect so I asked if the service was down. The attendant restarted
the router and I no longer had trouble connecting. 99% of the time I
have no problems connecting to a variety of wifi hotspots. I never
connect for any reason using MS Windows because I don't like taking that
kind of risk. So Yes I only connect using Ubuntu Linux.