Menu bars are not available in Photoshop 6.0.1

Today morning i installed Panther into my Photoshop. Once the installation process gets completed i restarted Photoshop 6.0.1 and it opens up in a classic startup and i wondered that there is no menu bars are available on the screen. I can't able to find where to fix the problem.
I did not face such problems before and this is the first time am experiencing this issue.
What could be the possible solution?
