LaTeX.org

This behaviour is pretty unusual and a remote diagnosis is very difficult. Choose a remote repository in your country (or at least the nearest) and try again.

Yes, thank you! Changing the package repository seems to have helped. I can now use setspace once again. Excellent!

However, I'm still ...

Just install the package(s) subsequently with the MiKTeX Package Manager. You can access it via Start menu.
Best regards and welcome to the board
Thorsten¹

Thank you! However, my problem is not resolved. I opened the miktex package manager, clicked the + sign next to "setspace", and it goes into ...

I've used TeXnicCenter before on a different computer, but I'm having trouble getting it to fully work on this one. For background, I'm running windows vista on a fairly new dell laptop, and my internet connection is working.

Here is what I've done so far:

I went to
http://www.texniccenter.org ...