windows 7 - Operating System on SSD but can't access files on HDD

Just upgraded from Windows XP to Windows 7 and added a SSD. The Windows 7 & Office is in the SSD.
I can see the HDD and my old files but everytime I try to access them e.g., word files,
It says I'm not authorised to.
I did not delete Windows XP from the HDD ( dont know how to ).
Can someone help me out please? Thank you.