I got this and followed these instructions. See if this helps.
The message was "Unable to send or receive messages for the <accountname> account.
Server Error: 0x80048849
Server: 'http://mail.services.live.com/DeltaSync_v2.0
.0/Sync.aspx'
Windows Live Mail Error ID: 0x80048849
We suggest that you follow the troubleshooting steps provided below:
1. Open Windows Live Mail
2. Right click on your Hotmail or other account and select Properties
3. Under the Server tab, look for Server URL
4. Change the URL from
http:// to
https://
5. Click Apply then OK
If the issue still persists even after following the steps above, please try the following:
1. Close Windows Live Mail
2. Open Internet Explorer
3. Go to Tools > Internet Options
4. Click on the Connections tab
5. Click LAN Settings
6. Uncheck the option Automatically Detect Settings
7. Click OK
8. Click OK
After following the steps above, we suggest that you relaunch Windows Live Mail.