Just downloaded the Add-ons from Bethesda's site (Horse Armor, Vile Lair, etc...) before noticing the Vista incompatibility issue (my own fault, to be sure). It seems like it would be so easy for Bethesda to fix just by offering the add-ons as files rather than putting them in a self-installer...?

I'm looking into downloading them onto my older desktop and turning them into OMOD's, but I'm still new to the mod manager. Is this the only way to get them on my Vista computer, or has someone else already made OMOD's of them all so I wouldn't have to go through so much trial and error?

First, even if someone had them in an omod, or already extracted format, they couldn't legally give them to you. Second, it probably wouldn't help you even if they did. The Vista issue, atleast as I understand it, is related to how the liscensing for these mods gets set within your system. You don't simply install just the mod, you install measures which allow that mod to function (as a means of preventing people from stealing those mods). Vista disallows this since it has tighter controls of what can be installed by people without admin access, and even restricts what people with admin access can do.

As far as I know, there is no simple fix, but your best bet would be asking Bethsoft directly, rather than trying to get around their security "features". It is afterall in their best interest to make their mods work with Vista.

I made the same mistake and Beth support completely ignored me though why I have no idea. You can do the OBMM on another PC that is XP and then move back on Vista if you don't mind the work involved. Or you can do what I did and get the Knights of the Nine CD for around 20 USD and install directly from the CD. I don't know why this worked for me since the files look exactly the same and I can't guarantee that if you choose this method it will work for you too. You could first try and copy the files to a CD (for archival purposes) and see if they install from there.

Interesting, I never encountered this problem when i downloaded Battlehorn castle, Or any patches. ( you would think it would affect the patches also eh'? )
In all seriousness, Did you ingnore there message and try installing it anyway?

i did download battlehorn during the one week bethsada was giving it away for free.
all the other stuff i did just buy Knights of the Nine.

The patches went through A-OK... it was just the add-on content that keeps getting rejected. I've e-mailed bethesda - we'll see what happens. If they can't get me copies that work, its off to find a KOTN cd with all of the add-ons (save battlethorn, but I hear its kinda shabby anyhow).

The issues I noted above pertain only to minor content like spell tomes and horse armor. Batttlehorn and official patch was no problem for me. There has to be some fundamental difference in these file types since one type worked and the other did not.

If you extract them on a non-Vista computer, you can just manually move the files to your gaming computer. No OMOD necessary.