I notice some people been having troubles about Dawnguard not working, and so do I. I'ma explain a bit of what happened to me and see what prolly caused it and maybe get some help to fix this cause I rly wish to kill some frekin Vampire Lords badly...

Okay.. So my originally problem was Dial-Up, which I have at home.. Well, I went to a funeral Friday's morning and was planning to hang with someone of my family for the day. I took Skyrim, Halo: Anniversary, and my Hard-Drive with me. After the funeral, I was able to connect my Hard-Drive to my family member's Xbox then was able to connect to XBL for first time on this Hard-Drive.. Created a GamerTag real quick (Which is Jusey01, if you wanna go check out for yourself to confirm my story) Then it updated my Xbox Dashboard stuff automaticly, which I was surprised of.. (Well this happened before I created my XBL account and etc).. After that was done, I updated Skyrim and got the latest patch then used a Redeem Code I bought from GameStop and got Dawnguard. After that, I use some other Redeem Codes that I had on me for a long time for other games and played Halo Anniversary Maps Online (Free 2-Day-Gold-Memship and very first time playing a Xbox Game online... And first chance to do it so I did it)..

After that, went back home and when I connected my Hard-Drive to my Xbox at home, I notice my Dashboard went back to an older version (One without the Avatar) but when I put Skyrim in, I had to update to play Skyrim (Which only rly brought back my Avatar...) Then I played Skyrim and notice that Dawnguard wasn't working... (The Patch WAS working and gladly do love the Mounted-Combat and new Kill-cams).. So yeh, Dawnguard not working even though when I get on it does says "Loading add-ons" real quick then gets done... I also have 50/60 Skyrim Achievements now which rly just mean I got the 10 new Dawnguard Achievements on my list to do...

So.. What you think? What could've caused my problem? Any solutions?

maybe u need to be connected to Xbox live to play dawnguard

If you are not connected to live you will not be able to play the add-on as the licence to play that DLC is only granted to the console you downloaded it too, if I get what you said right, you took your HDD a put it in someone else's Xbox and purchased Dawnguard.

If that is the case your Xbox Live account has a limited right to use this content, but only while connected to Xbox Live

To fix this you will need to use your Xbox and PC/Laptop to perform a Licence Transfer (1 use per 12 months) with your Live account signed in at xbox.com

~Edit~

Okay. Just read this license and thx you for telling me about this.. This is first time of hearing about this... And I can still take Microsoft to court for not properly telling me about such licenses...

Sadly, cause of my Dial-Up connection and my computer connection, I cannot properly go on Xbox Live to transfer such licenses.. Only way for me to do such things would basicly be via USB (Like how I got my Dashboard update today)... Or just get lucky again, which would be almost impossible unless I annoyed the heck outta someone... And that would just cause more issues..

Dude, you need to do a licence transfer. Your HDD was connected to a different xbox 360 when you downloaded it, so THAT 360 was marked as the primary system meaning only that console can play it without connecting to xbox live.

Every single piece of DLC is like this, as are all xbox live games (bar avatar games) and have been for years. You are mistaken if you think it is otherwise.

Only by performing a licence transfer to YOUR 360 console will you able to play offline.

I am not sure if the US purchase steps are the same as on the UK one, but Dawnguard was the first DLC to actually give me a on screen warning that it will only work on the system downloaded to.

that happened to me 2

When I put in the code, all it said that this code will allow you to download Dawnguard and do you wish to use it now.. Didn't explain to me about the whole License at all.

1: 1st time ever being on Xbox Live, period. So I had no idea whatsoever about anything online.

2: Please be a little nicer.. Your post kinda does have a 'mean tune' to it.

3: I know what to do now and will be fixing it here soon, I hope.

~Edit~

How do you even do a License Transfer anyways?

http://support.xbox.com/en-GB/xbox-live/marketplace-and-purchasing/download-content

Oky. I'm taking my WHOLE Xbox to a friends house this Thursday and fix all of this.. I'ma hope that does the job.

It may just be something like a new law requirement in the UK to explain the licence terms then.

I fixed it anyways. Gonna request a lock.

OP requested close as solved.