Try the mount command without the -t parameter as in:
mount /dev/sda1 /mnt/win
First make sure that /mnt/win exists.
If that doesn't work then try looking in /etc/fstab to see if there is an entry for /dev/sda1. It could have bad options.
If that doesn't work then try using verbose mode with the mount command as in:
mount -vf /dev/sda1 /mnt/win
The last form fakes a mount (-f) but supplies some information about the mount process (-v).
Lastly try a regular mount one more time but add the option for read only mount:
mount -o ro /dev/sda1 /mnt/win
Let us know if any of this helped.