It sounds like the worksheet may be protected, which can prevent changes to the print area. Here are some steps you can take to try and resolve the issue:

1. Check if the worksheet is protected. Go to the Review tab and see if the "Unprotect Sheet" option is available. If it is, click on it and enter the password if prompted. This should allow you to make changes to the print area.
   
2. If the worksheet is not protected, try selecting a range of cells that you want to set as the print area. Then, go to the Page Layout tab and click on the "Print Area" option. From the drop-down menu, select "Set Print Area". This should define the selected range as the print area.
   
3. If the "Print Area" option is still grayed out, try going to the "Page Setup" dialog box. You can access this by clicking on the small arrow in the bottom right corner of the "Page Setup" group on the Page Layout tab. In the "Page Setup" dialog box, go to the "Sheet" tab and check if the "Print Area" section is grayed out. If it is, try unchecking the "Print" option under "Print Area". This should allow you to define a new print area.
   
4. If none of the above steps work, try saving the file as a new workbook and see if the "Print Area" option is available in the new file. If it is, you can copy and paste the data from the old file to the new one and define the print area there.

I hope these steps help you resolve the issue with the print area.