No sound from laptop speakers nor headphone

Hello,

My Toshiba laptop has been running on Window XP for 3yrs and it says it is widows Vista capable. I just recently noticed that I have no sound after my last Microsoft update. Yet, my other two toshiba laptops which are newer and run Vista have no problems. I tried to do a system restore but it was turned off, so now the only restore point is today. I tried system properties but it says the hardware cannot be found, and the volume window is grayed out and will not let me adjust.

Please help,