I'm not sure if you guys have this problem but I tried repairing my combat ranger helmet (the one on the game cover) and I couldn't repair it because it has a value of zero. Are there any fixes or is there an alternative way to repair it?

Buy Combat Helmets

I dont think you can buy them. There only found on the ncr ranger veterans

Hehehe, No, regular combat helmets. they usually range around 300-400 caps at the Gun Runners.

A couple of things that could be possible: Your repair skill is too low to repair it any further than it is (or it's already at max condition). If you do have 100 in repair then the only other thing I can think of is that you don't have the correct item to repair the helmet and you either need to take the jury rigging perk or need to take it to an NPC with a higher repair skill.

You're confusing New Vegas with Fallout 3, Obsidian threw that concept out the door. You can have a Repair skill of 1 and still fix an item to max condition, in New Vegas, Repair determines how long an item can last before destruction. His problem is his repair is apparently not at 90, which bars him from Jury Rigging, which is arguably one of the most useful perks in the game, without it, repairing an NCR Ranger Helmet is restricted to Combat Helmets, which are easiest purchased at the Gun Runner booth on the East Side of Vegas.

Jury Rigging!

Oh no! My Ranger Combat Helmet is at 10% condition. What will I do?

*picks up pair of reading glasses and duct tape*

Good as new!

Jury rigging is the solution!