Unable to boot-up Windows

[SpecialK_22]

I use a separate boot-up session when I turn on the computer. It's either Ubuntu Mint or Windows. Well Windows worked fine two nights ago, and I shut the computer down with no problem. Now that I try to boot-up windows, I have a blank screen with a flashing dash in the upper left corner of the screen. I'm not able to do a command or anything and the longest I've wait was 20 min. Not sure why it's doing this, but could this be a sign of a virus within Windows? Since we have no anti-virus or any type of security, because we been using Ubuntu itself.

 

[nhasian]

you can still boot into Ubuntu correct? try scandisking the windows partition to fix the problem. bare in mind that if you use the windows cd to repair windows it will clobber the grub bootloader and you will have to manually reinstall grub to get back to ubuntu.

 

[SpecialK_22]

How did I get a GRUB though? I mean I was able to access windows fine until just the other day, and yes I can still boot-up into Ubuntu itself, tried installing wine so I wouldn't have to go into windows, but that is also confusing.
Anyways, I'll try to do a cd to repair it, though another question ;3 How do you manually install grub again? This is basically all new to us.
Thanks~