After much time trying everything I could find here and elsewhere, to permanently restore column headers in Windows 7 Explorer details view (short of restore point or repair install), I've given up. Maybe someone can shed more light on this, or somehow use what I've learned...
I tried resetting of folder settings, with registry removal of Bags and BagsMRU (ala Windows_7_Reset_All_Folders_To_Default_Folder_Views.bat -- thanks, Shawn -- and even added more for good measure), did many registry exports (to compare what little I could fathom), various changes and restarts, etc., but nothing corrects it permanently, except if I change ClassicViewState back to 0 (the default; in HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\Advanced).
I wanted ClassicViewState=1 so I can set a sort order on one folder, and have it instantly used for subsequent folders I view, without having the trouble of using Apply To Folders, like with good old XP. (As suggested at http://answers.microsoft.com/en-us/windows/forum/windows_7-desktop/windows-7-do-not-remember-folder-view/b88dfdbd-3491-4088-97a4-c620e17c6985
and elsewhere.) Is there a better way to do this than setting ClassicViewState? Is there a keyboard shortcut for Apply To Folders?
[ FYI, ClassicViewState=1 seems to work fine on a couple other user accounts on the same machine (so far), even after viewing photo folders, but on my account, I consistently lose the column headers in details view. Note that clearing Bags, etc., does bring my detail view back to normal, temporarily, but as soon as I view a folder of pictures, and then go back to another folder with details, the column headers are gone again. This might have all started after I made some other changes to thumbnail caching/location, or other Explorer tweaks, I am not certain. But reversing those changes doesn't seem to help. It does appear like a real bug, and I wish MS would fix it. ]