For those having problems saving files, try saving to a different location, such as your desktop, a flash drive, or your my documents folder.
If you are still having the error, try cleaning out your cache, FF users can simply press Ctrl + Shift + Del, under "time range to clear" select everything, and make sure cache is checked, then press clear now.
Then try downloading again.
If that still does not work, it may be your internet connection. Try disconnecting your router, wait for 60 seconds, and reconnecting. It may also help to run a DNS Flush by going to start, typing cmd, press enter, type ipconfig /flushdns. It also wouldn't hurt to type ipconfig /release, and ipconfig /renew.