I've got a strange problem that I was hoping some of you had heard of.

If I go to the main page of the website (really, whatever page I initially visit), everything (header, etc.) fit on the screen normally with no horizontal scroll bar appearing. However, if I click a link on that page to another page of the website, when that page loads, the header (same header on every page) will now be a little longer than the screen and a horizontal scrollbar will appear. If I hit refresh, it goes back to normal (everything fitting on the screen).

What could be causing this?

Thanks!