First off lets assume anyone reading this, including myself, already knows that you can't read multiple copies of the same skill book and get a skill increase everytime. One copy of a skill book equals one skill increase, second copy of the same skill book equals no skill increase. The official stradegy guide and all wikis state that there are 90 skill books total with 5 for each skill. There are copies of these books though so the total amount of skill books in Skyrim is well over 400 supposedly.

Now for the purpose of this thread. Myself and a few others have been noticing that new skill books that should increase your skill aren't working. These books in question haven't had any of their copies read beforehand. At first, I thought it was a glitch, and that may very well be true, but looking further into this I found soemthing interesting. What the wikis and guide say might not be true about how skill books work. I was hoping someone might know the truth about how they really work. What I'd like to know is are there any restrictions on getting skill points from books after a certain skill level? Are there exceptions where you can't get a full five skill levels from the five different skill books in one skill type?

I found this in a forum and would like to know if there's any truth to this:

"Forget the number that's in the strategy guide. You are allowed x amount of skill increase per skill via books once x amount reached than no more level increases. There are far more skillbooks vs the cap."

If this has any truth to it, can anyone elaborate on what it really means in english and not algebra? Maybe the problems I am others have been having are just glitches? Thanks for the help.

Every book has an option in the CK (or rather did in the CS/GECK, so it'll be the same) to "teach" something. You can select a skill from the dropdown menu and when you read the book the game will increase that skill by one level, and will then record that you've read the book and won't increase the skill if you read it again.

Each book has a base object, that's the actual book. References of this book are then placed in the world. So regardless of if you read a "different" copy of the book, it's the same base object, so the game won't increase your skill again.

Someone saying that skill books are based on x amount of reads is rubbish.

Okay that all makes sense, thanks. What I'd really like to know then is in a perfect game without glitches, you should be able to get 5 skill points per skill by reading the five different skill books for that skill? right? So if you read all 90 different UNIQUE skill books, you'd have 5 skill points added per all 18 skills? Is there a reason that isn't working in my game then? I have found all 5 unique skill books for many of the skills and only a few gave me all 5 points. In fact, the 5 unique archery books only gave me 2 skill points, because three didn't work. None of the books were of the same volume, all were unique. Is it possible that a developer didn't add a skill in the dropdown for certain books in the CK? Other than that, what else could cause this? Sorry, I know the way I'm asking these is probably confusing. It's just frustrating that many skill books won't work for me even though they 100% haven't been read before. In fact, in one case, the block skill book (Battle of Red Mountain) at North Skybound Watch didn't work for me. I reloaded a save from 20 minutes previous and ran straight for the book and then it did work. I reloaded the same save again, did some stuff for about 30 minutes (no skill books though), went to that block skill book again and it didn't work again. Very frustrating. Maybe it is just a glitch in my game.

5 points per skill book? Um, don't I get one point?

Sorry but where did you get that from? I clearly said one copy of a skill book equals one skill increase, second copy of the same skill book equals no skill increase. One point per book. There are supposedly five unique books per skill which when all read would equal five skill points earned for that skill.

From two of your posts:

1) "90 skill books total with 5 for each skill"

which I thought was odd. So i read all of what else you had to say. Then you posted:

2) "So if you read all 90 different UNIQUE skill books, you'd have 5 skill points added per all 18 skills?"

There's no need to apologize, but my mild confusion does come from you and what you posted.

By your readtion, I see that you meant it the other way round, that 5 points are possible, total, from 5 individual books for each skill, not that a single book rasies a skill 5 points

I am not great at explaining things, so my bad. This whole thing is a bit confusing. Just want to know why skill books that should be working aren't.

You didn't explain it that badly. I took the wrong idea and ran with it

If your using a mod to slow down the rate your skills increase, you might find this happens depending on how the mod works.

If it's done using perks the same way that the guardian stones are implemented, and if the total rate of skill increases is anything less than standard, then reading a skill book when your progress towards your next increase is low will not register as a skill level increase. That is, there will be an increase in progress to the next skill level, but that increase is not enough to raise the skill to the next level.

Next time you open a skill book you haven't read before, check the skill progress indicator before and after to see if progress increases. If so, then chances are that this is why.

As it is, if your using no such mod (skill rate 1.0), and you have a guardian stone active for the designated skill (skill rate 1.2), and your have the Lover's Comfort bonus (skill rate 1.15), then reading a skill book will increase your skill by approximately 1.38 skill levels (1.0 * 1.2 * 1.15). If all 5 books for a given skill are read in this way, then you can actually gain 6.9 skill increases in total. This is the same reason that people see progress in skills that they've never used even once.

Basically, skill books do not raise a skills level. Instead, they give you one standard skill level worth of skill progress. Bonus multipliers are applied after this, before it is applied to the skill itself.