Okay, I'm sure I've installed OBSE correctly, I've read, re-read, then read some more the instructions on how to install for the Steam version of Oblivion.


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From the v0017b ReadMe:


If you are using the Steam version of the game:

1. Copy obse_1_2_416.dll, obse_editor_1_0.dll, obse_editor_1_2.dll, and obse_steam_loader.dll to your Oblivion directory. This is usually "C:\Program Files\Valve\Steam\SteamApps\common\oblivion".
2. OBSE will automatically be run along with Oblivion when launched. To disable this, rename or move obse_steam_loader.dll.


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I tried a very simple OBSE plugin (Denock Arrows) as well as some more advanced ones like Scorn's Vampirisim and Curse of Hircine, none of them worked. I got script failure messages from Curse of Hircine, nothing from the others, but when tested they didn't work.
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I'm running Vista x64 SP 2.


My Steam Oblivion folder is: C:\Program Files (x86)\Steam\steamapps\common\oblivion

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Link to my other topic about this:

http://www.gamesas.com/bgsforums/index.php?showtopic=1076628&st=0&gopid=15672397&#entry15672397

I already posted a solution on the other thread...