I first noticed this when I tried to get Windows 8.1 for my Dell XPS 8700 recently. The Store wasn't connecting, even though I tried every solution possible. The I checked if the crappy Mail app was connected. Right away I see in the top-right corner: *** Email address is removed for privacy *** is unavailable. Then I tried to just download the installer and run it, and guess what? Can't connect! Then I realized: Nothing Microsoft can connect. I remember that this has been going on for the longest of times: the Mail app couldn't get Microsoft account mail since I got this thing.

I would like to know more information about the issue so that we could assist you further.
1. What all troubleshooting steps have you tried to resolve this issue?
2. Are you using any proxy connection to connect to Internet?
3. Do you get any error code or error message?

I would suggest you to try the following methods and check if it works for you.

Method 1:
Run the Microsoft Account troubleshooter and check if it helps.

http://go.microsoft.com/fwlink/?LinkId=268424

Method 2:
If you are using any Proxy connection, then try disabling the proxy connection.

Follow the steps to disable proxy:
a. Click the Gear box at the top right corner in internet explorer.
b. Click the Tools button, and then click Internet Options.
c. Click the Connections tab, and then click LAN settings.
d. Uncheck the option “Use a Proxy Server for your LAN”.
e. Click Apply and Ok to cave changes.

Method 3:
Place the computer in clean boot state and check if the issue persists. Clean Boot will help you determine which third party app/program is causing this issue.

How to troubleshoot a problem by performing a clean boot in Windows Vista or in Windows 7:
http://support.microsoft.com/kb/929135

Note: After clean boot troubleshooting step, refer to the section "How to reset the computer to start as usual after troubleshooting with clean boot" in the provided link to return your computer to Normal startup mode.