a very anoying glitch keeps happening, i have a model with 2 normals inside out causing black spots (used to be like 100 and every time i fliped them all at once this glitch undone all my work and i had to start again so i saved just befor i finished) and as soon as i flip them to the correct position to get rid of the dark spots, like ide sub divide right so i can start sculpting and as soon as i pressed control z to undo a sculpting move it reverted me back to its original state from the last save with the normals unfliped and un sub devised, but if i press ctr z any time before i start sculpting it works fine and just goes back one step please help i nearly broke my computer after it happened twice with 100 normals to flip…
First off - punctuation, second - did you recalculate normals (Ctrl+N), or did you try flipping each inverted face seperately?
i used ctr N ctr shift N
I think you’d have more chances by having your post placed in the support section… Maybe the Moderator will slide it for you?
Best luke, anyway.
And perhaps can you provide a screenshot or (even better) a .blend file?
… fine… >.<… but no one can use this model for there own personal use since im using it in a comercial product, to get the glitch, ctr N or ctr shift N the poly on inbetween on the top of the mask on the right of the nose and the back of the neck on the top of the mask then subdevide a bunch of times and try to sculpt, then press ctr z
http://www.filefront.com/17267525/prettyy-plzzzz.blend/
Ok, i see the problem right away… You should never join faces in this fashion:
You can see it where the head connects to the hat, and where the sleeves connect to the arms. Also have in mind that faces have only one side. Places like the rim of the hat will show up only on one side, so it also has to be given some thickness. Third (not related to face normals), your model is not perfectly symmetrical, if you go into front-ortho view you will notice that the symmetry line is not straight. Consider using the Mirror Modifier. I can fix it for you so you can compare, but it would take some time.
the non symetry is cause because the model is slightly rotated… lol, go top view alight the thumbs along a line, think youll find it goes away, and ill try the thing, but im not sure how effective it will be at fixing the auto erase glitch, im pretty sure its more to do with sculpting rather than a normals problem, its just annoying flipping the normals again when if happens
I played with the file a little, because I had nothing else to do right now. 
I fixed all the problems I spotted (mostly those pesho mentioned) and added a few loops here and there to make it subdivide nicely. Anyway, I just did this for my personal enjoyment, so don’t sue me if it doesn’t work for you. Here’s the (new) link:
http://www.filefront.com/17267789/prettyy plzzzz 2.blend
link dun work nun 
awww
Not counting the symmetry, it’s a topology problem, the mesh needs to be either a convex hull or a shell, not something inbetween like with the hat. If everything is as it should be, recalculating normals should work without a hitch and you won’t have to do it manually. I also had nothing to do, so i also fixed everything including the symmetry 
http://www.filefront.com/17267778/maskedguy.blend
Compare it to the original and you’ll see what i mean.
I uploaded again at filefront and changed the link. Still wondering, why paste-all.org is blanked, though…
thanks that worked