Figured out solution as in previous version of iTunes I had changed the iTunes library location hence with the new install it was the ituneslibary.itl file which wasn't there now. Just copied old version of itl file and it worked.
Restoring your iTunes Library backup
When you need to restore your backed up iTunes Library from your external hard drive to your computer, follow these steps:
Locate your external hard drive.
Mac: On the Desktop or Finder sidebar.
Windows: In My Computer
Drag the iTunes folder (backed up earlier) from your external hard drive to whatever location you desire on your internal hard drive. It is recommended that you choose the default location for the iTunes folder, which is:
Mac OS X: /Users/username/Music
Windows XP: \Documents and Settings\username\My Documents\My Music\
Windows Vista: \Users\username\My Music\
Windows 7 or 8: \Users\username\Music\
Open iTunes while holding down the Option key (Mac) or Shift key (Windows).
In the resulting dialog, click the Choose Library button.
Select the iTunes folder you just moved to the internal hard drive.
Click Choose (Mac OS X) or Open (Windows) and then choose the iTunes Library file inside .
After following these steps, iTunes will open and your iTunes Library will be restored.