I'm not sure if I deleted it by accident but my Skyrim high res texture pack is gone. I went to steam and said I wanted it, it had me log in and said to start skyrim and it would install then but it didn't. I see no HighResTexturePack01.bsa in my data folder. That is where it should be isn't it?

How do I make steam re-download it? I think I "unsubscribed" from it or something and that is how it deleted the files from my disk.

I don't think it's possible to unsubscribe from the DLC, it's not handled through the Steam workshop like regular mods.

If you right click on Skyrim in Steam, go to properties and then the local files tab, there's an option called 'verify integrity of game cache'. If you click that it should restore any missing files, which I think includes DLC.

Yes but won't that overwrite my skyrim.ini and any of the scripts I've edited for mods I'm making? I guess I could backup my whole folder to be safe.

Make a backup of the scripts for your mods, and make a backup of your ini file, or any modded file that has replaced a stock file, because it could restore that back to default. i own gmod and have so many mods installed for it, verifying the integrity of game cache doesn't remove added files, it will replace corrupt and missing game files you get with the game, and that can include official scripts that came with the game that have been altered. Added files for Mods are left untouched from what i have seen.

I have ran this on every game i have bought on steam, many of those games have added mods installed, none of those mods replace stock files that i know of, and those mods are still working fine. It normally only messes around with official game files that come with the game.

It will overwrite your INI files, back those up.

However, any mods or other files that Steam does not know about, it should ignore. That would include any mods from the Steam Workshop as they are handled differently than the DLC (which is what the texture pack is).

BTW, the only way to get the DLC really uninstalled from your game is to send an email to Steam and ask them to remove it from your account.