I modded my gamerscore for Guitar Hero 3 a year or so ago and I still havn’t been reset even though I didn’t timestap the online achievements? Has this case happened before where people don’t timestap online achievements and get away with it? And does reputation and tenure effect the likelihood of being reset? My tenure is seven years with over 70,000 legit gamerscore and would hate to see it all go to waste 
If you mod your gamerscore, no matter how many precautions you take, there is still chance of having your gamerscore wiped.
If they catch you, they will change you gamerzone to “Cheater” (you can’t change it) and you will have 0 gamerscore. All achievements that were previously unlocked, will be permanently locked meaning you’ll never be able to earn those back, legit or otherwise.
Do NOT mod your tenure. That has a 100% ban rate. If they wipe your gamerscore, but your tenure is legit, you’ll keep your tenure.
Source: I have a 10 year legit tenure account that has had its gamerscore wiped.
Is there a way to fix this, such as re-unlocking them with the timestap on today? Would it sync to the servers and remove any chance of me getting detected?
If they’ve already synced to the servers once, you’re SOL.
I assume this has already happened since you modded those achievements a year ago. Unless you haven’t signed into XBL since you modded them.
I’ve been playing ever since, never stopped. Will I ever be caught, or do I just wait until 'judgement day" by the M$ lords?
I can’t answer that question. I modded around 40k score to my account, and I was all good for about six months. Then I got reset out of nowhere.
Some people mod much more and are fine for a year. It’s pretty random. If you don’t want your gamerscore to be reset, don’t mod it. Period.
Since you unlocked online achievements without timestamps I guess there’s only a matter of time before you get reset. 
Thanks! I was also curious about how the process to find illegitimate gamerscore works, such as sniffing out these profiles and are the investigations manually made?
Well, one easy way is to filter all players in a black list if they somehow obtain online achievements offline. Because it’s impossible…
Players can view your profile / compare games and if they see you have unlocked achievements in the wrong order, etc they can file complaint your account for cheating.
And also if you sign-out of your account mods GS and log-in ten minutes later with 3,000 more GS.
You get the drift.
Pretty much when modding you gotta just make sure you don’t make it obvious. So when doing it properly takes time pretty much huh. And I have an account called " sus7ainable" I modded about 2 years ago when I had Xbox 360 and I still have the gs it’s only 12k tho.
Exactly. A few achievements a day, space them out, take your time and chances for getting caught is slim… When I started messing around with the achievement unlocker back when I signed up I had no idea what I was doing lol. Let’s just say. My gamerscore is over bro… 
lol, gamerscore, who cares.
I used to care about it. Just because you don’t care about gamerscore doesn’t mean everyone else have the same opinion. Check out TrueAchievements, 250.000+ achievement addicts and the site is growing strong.
Do you even know how much dopamine your brain produce when you unlock a hard achievement or get the full 1000/1000? No wonder it’s addicting. God it feels amazing.
Yeah so I also have some gamer pics which I downloaded from horizon, so when they investigate me and I have it on, will I get perma banned for marketplace theft?
No, haha. Don’t worry about downloading and using gamerpictures.
Hypothetical if I were to load up another version of my account with different achievements locked and unlocked, the locked achievements wouldn’t change the originally unlocked ones and the “newly” unlocked ones would update right?
It’s just a matter of time and unfortunately my friend, there’s not a thing you can do about it, except wait…
How long? you ask…
They caught up with me over 4 years after I had a fiddle with my achievements and I did everything the “RIGHT” way and took as many precautions as possible and never went overboard.
That’s right, over 4 years later… So expect it, when you’re not expecting it…
Sorry Mate, but there’s no happy ending for you.
if you dont want to be reset then hide your game history or at least set it to friends only but hiding it from all is the best way of preventing a reset in your situation (obviously it dont prevent reset if you do something stupid like add 50000g at once )
This may sound like a dumb question, but on another thread here people were giving another person a hard time for mysteriously having unlocked all achievements for TF2, mocking him for “pretending to be innocent”. So, is it possible that he was actually banned for such a decision?
For the record, I have NOT used any unlockers yet, let alone screwed around with hacks on VAC servers (though I did get a very funky mod that makes the medic flip everyone off when using the MTM taunt), but Offline Mode tends to screw around with achievements. For example:
Walking Dead, 100% clocked, no achievements.
Bastion, 100% clocked, only missing “finished game” achievement (despite having "finished New Game+ Achievement)
Darksiders, Completed Story mode on Normal, Some achievements have not unlocked (notably ones otherwise impossible to miss)
While I know it’s not the end of the world or anything, I’d like to know that I can get the achievements I “deserve” (yeah, I’m gonna get mocked for saying that) without being punished for it.
Actually, now that I think about it, this IS bloody a dumb question since VAC bans are only for multiplayer games XD. Um. Perhaps someone would like to confirm that doing such a thing, like for TF2 or CounterStrike, can or can’t get you banned? Now just out of curiosity more than anything, I suppose
Update: So I’ve downloaded one and used it to unlock that pesky “finished story mode” achievement on Bastion that I really didn’t feel like playing the game a forth time to get. 100%, yay! I have to admit, it’s pretty damn tempting to sweep down some achievements I just plain don’t feel like getting (e.g. Wonderful End of the World: Explicately reset the game and play to the last level in one sitting. Really?). But meh.
Thanks to everyone who posted.
has no way to delete achievements