What exactly causes a skill to drain significantly and go red (and a much lower value) when there are no diseases or other discernable outside factors or negative active effects involved? I've had this happen at lower skill levels and fixed it by training the skill up at the next opportunity.

Recently though, it happened on the progression from 99 to 100 for archery, and dropped the skill to 15. I was unable to train it away, and no amount of console commands would budge the value from 15. I ended up reloading an old save and when I leveled from 99 to 100 again, it worked as normal.

One thing about the reload, I was able to closely recreate the exact leveling scenario, as I was doing the Archery practice thing with Angi, so I was able to closely control when I leveled and not level randomly in combat. Intrigued by this, I reloaded and went through that controlled leveling scenario four additional times, and out of those four additional tries not one of them went red on the jump from 99 to 100.

So what causes skills to drain into the red in the first place? It's an odd, unexplained game mechanic. The fact that the number goes red implies some intentional design and not just a bug, although with unintended results if it happens at the 99 to 100 jump. Search has yielded mostly conjecture around forcing use of trainers occasionally, and "are you diseased?" comments.

I'm on PC - I assume this affects XBox and PS3 as well.

I saw one of my skills go red. I hope it did not go down.

Did you lose some of your fingers in combat? Maybe you can't draw as much now

A skill will turn red when its base value is lowered.

This is usually caused by diseases and in the previous games their were skill/attribute drain spells (but dont remember any in skyrim)

Sounds asthough it could have just been a simple glitch that is hard to repeat

I think it is a bug from some time when skill damage was still in the game. I thought I got it from fighting a Thalmor one time, but I am not sure exactly where it comes from. As far as I know it only happens with Archery.

i have the same problem in 2 handed skill it went to a red 15

I've read that they glich shown level sometimes. Once you level up that skill your actual should show up. If not, you sir have the clap. I just noticed the 100 part. Idk have you tried changing all your gear and or weapons. Maybe something your wearing is doing it

I think it actually is some kind of bug - I had it happen to me with my One-Handed skill. It dropped for no reason from the upper 50s to 15, and wouldn't move up as I trained the skill. No active effects or diseases causing it that I could see, and every console command I could find to remove diseases, spells, etc. had no effect.. Just like you I had to reload a previous save.

I had a couple of instances of something similar in Fallout 3, except there I was teleported to right outside Vault 101 with all my skills at 15. Reloading fixed it right up, though.

I had my Archery skill drained to 15 for unknown reasons. I tried to sleep, change gear, level up, cure decease.. nothing worked.. so I reloaded an older save. :/

I had this happen with my 1H skill. I had a notice that I leveled up. I went through another cell ( maybe several ). I was getting 1H training. After training I leveled up my char and got some more training. I went back through a cell and my 1h was in the red. I reloaded raised my level, entered the cell , got the training, left the cell and everything was fine.

It seemed to be tied to the combination of leveling and training. I repeated the initial steps and it was still red. When I did not forego the initial training and just leveled first. Everything was fine. Now i train before I am about to level. Then the training levels my char. I level up and train some and everybody is happy.

is there a way to fix it

You have to raise the skill one point, the quickest way obviously is training. However you can't do this if you are at 100. I think it is just a display bug. I don't think the skill is actually at 15, but I could be wrong.

same thing happened to me i have no idea why

My weapon damage went down. That's how I noticed it the first time. I didn't try to raise the skill after the fact. I just loaded an earlier save.

Guys this happens to me often and what make me awhere of it is..someone says..Quote! pardon me for saying this !BUT YOU DONT LOOK WELL, it was'nt till I went to another town they said some thing along them lines.. AND it means you have been poisend or affected after battle...Just go to the shrine of althos..or what ever its called and get healed the RED goes..easy. Ihave had it in loss of single handed, loss of Stamina, and just plain poisend.

OK, thanks for the info.

That is true, however in my case poisoned or illness was not the issue. I was fine just prior to the combination of entering the cell, leveling and training. Nothing happened to me prior to just going through the door.

I had the bug with ever training, ever.