Cannot collapse headings on default.

[Alisena]

I used to be able to collapse my heading by default. Now I can't. The box to check it in is grayed out. Meanwhile in some of my files it stopped working after I opened it in a different computer. Some files I never touched. Either way, how do I collapse by default again?

[Stefan Blom]

The file is probably saved in an older version of Word which doesn't support collapsing and expanding headings in Print Layout view. Click File | Info | Convert.