OK, as everybody who has downloaded something on Snow Leopard knows, for most files you download when you try to open it after downloading, it will pop up a nice little dialog box saying that the file was recently downloaded from the internet and are u sure u want to open it.
Unfortunately this is not strictly neccessary - and is rather annoying for some file types (Especially NZB's).
The fix for this, is to create a plist file inside ~/Library/Preferences called com.apple.DownloadAssessment.plist with either TextWrangler, or the Property list editor.
If you are not comfortable creating plist files by yourself, my DownloadAssessment.plist file can be located here:
com.apple.DownloadAssessment.plist, and you can just drop it into Library/Preferences under your Home Directory. (If you wish you can open this with something like TextWrangler, and verify that it looks exactly the same as below.).
The file should contain something similar to the following contents.
CODE:
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
<key>LSRiskCategorySafe</key>
<dict>
<key>LSRiskCategoryContentTypes</key>
<array>
<string>public.xml</string>
</array>
<key>LSRiskCategoryExtensions</key>
<array>
<string>amz</string>
<string>nzb</string>
</array>
</dict>
</dict>
</plist>
NOTE: The amz extension shown above was allready marked as safe - at least on my system (you can remove this however), nzb is the one i have added.
All you need to do is add any file extensions that you don't want to be flagged as at risk, to the LSRiskCategoryExtensions section, and then add the UTI (Uniform Type Identifier) for that file extension to the ContentTypes section (FYI .nzb files are basically XML files hence the public.xml string). Note that if you are using a version of OSX < 10.5, then you can avoid listing every UTI, by simply using public.item as a string - unfortunately in 10.6 at least they changed the way UTI's are handled.
A list of UTI's can be found here:
http://developer.apple.com/mac/library/documentation/Miscellaneous/Reference/UTIRef/Articles/System-DeclaredUniformTypeIdentifiers.html
HTH,
Keith
