Microsoft changed the way USB flash drives are formatted in the latest dashboard update. Currently, Horizon will not see flash drives formatted with it. Expect a fix for this in a few hours! Until then, you can manually browse the contents of the flash drive using Windows Explorer.
Update: The latest version of Horizon supports the new flash drive format!
All fixed!
Good job guys for fixing this!
Nice! When M$ gives you lemons you squeeze them *****es in their eyes, and say we got this… All fixed.
Yes! Thanks so much. Microsoft can’t beat Horizon! 
Great! I really needed this update.
Great stuff as always!
Thanks! In fact I only logged back into this site after years (and resetting my forgotten password) because of the new update to the format. I was worried. In fact I’ve been using a 2012 vers of Horizon this whole time up to now (I just use it most for full game/DLC file transfers from a USB stick to my larger PC drive for archiving, especially with all the free Games with Gold, my old 20GB 360 has no room).
But now that I came back here… I need help! I was on the front page and clicked the big green “Download” button, but when the Save As dialogue popped, I got a “.WEBSITE” file. I’ve never seen that. is the site still under some construction and this is bug? Where do I go to download the latest Horizon version that supports the new format, as the changelog stated? (2.8.6.0)
Would really appreciate some help. 
Try downloading it from here instead
something has gone majorly wrong my end since ms and horizon updates.
i cannot upload any of my past or new maps to minecraft…
ive been doing this a long time and just got some new ones a few days ago
finally found time to install them, went through the full process 6/7 times now but whenever looking at the saves on minecraft all it says is file damaged???
any ideas guys?
I just modded a minecraft world save a few days ago after the updates and it worked fine.
Could you list for me the steps you’re taking in detail?
it wont let me get passed the installing it just stops there
Use the link below to download Horizon. It should download & install properly.
Download Horizon: https://www.horizonmb.com/client/v2/latest.php
hola soy nuevo aqui espero me ayuden pronto,mi problema es ke horizon no lee mi usb,ya esta configurada a mi xbox 360 rgh pues ya le he puesto skyns con esa misma usb,el problema es ke horizon no la lee porque???
English translation:
Hello I am new here hope help soon , my problem is ke not read my USB horizon , and this set my xbox 360 rgh as I have already skyns with the same usb , the problem is not read ke horizon because ??? ???
This is an English only speaking site. Please use a translator like Google translate next time.
Spanish translation:
Este es un sitio sólo habla Inglés . Por favor, use un traductor como Google translate próxima vez.
Are you sure that you’ve updated Horizon and applied the latest Xbox 360 update to your RGH somehow?
Spanish translation:
¿Seguro que has actualizado Horizonte y aplicado la última actualización de Xbox 360 a su RGH alguna manera ?
Happened to me too. I can’t even rehash and rehash my old save games to my own profile, they even end up corrupted or even load up.
Pasen Link de la actualizacion
Guys i download new Horizon and its wont open to me,any suggestions? its just show me big Icone on screen and nothing else …
yeah it’s happening to me with WWE2k14 i’m thinking and this is just me, i created a blank save on another profile, hoping it would restructure the device, then i copied just my wwe2k14 game save i was trying to add back on and it went to load it like normal till it couldn’t read any of the caws arenas pt etc cause they weren’t there. i think that’s what you have to do, make a blank save in whatever game you’re uploaded a save to the usb drive for, then exit out and add your files back onto flash drive with horizon.
EDIT: yep that’s what it is, you need a save file from whatever you’re trying to update from the game so that it can build the flash drive’s structure properly. after you do that, you can add files no problem. just saved my WWE2K14 99-01 wcw save lol
EDIT 2: my other saves keep giving me the error this is really frustrating as hell!!!
how do i connect a device to horizon?