After hours and many blogs later, I've discovered the extremely easy solution to this error message. I am on Windows Server 2008 / ColdFusion 8. Here's what I did:
1. Using the 32 Bit ODBC Administrator at C:\Windows\SysWow64\odbcad32.exe , created my ODBC datasource (in this case it was a .CSV text file)
2. Opened up REGEDIT and went to the HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\ODBC node and right-clicked it and chose EXPORT, saving the file to my desktop as importme.reg.
3. Edited the .REG file in NOTEPAD and removed all references to WOW6432NODE, so that the path was now where ColdFusion was attempting to find the DSN in the first place: HKEY_LOCAL_MACHINE\SOFTWARE\ODBC.
4. Save your changes to the .REG file, then double-click the .REG file to add it to your registry. By doing this, you create the non-existent node and ColdFusion can now see your 32 Bit ODBC DSN. Voila!
I've been installing ColdFUsion 8 on Windows 2008 R2 x64. I've had some success with a slightly different strategy, and arguably simpler answer:
When you install ColdFusion 8, make sure you right-click on the installer, and select "Run as Administrator".
You have to do this even if you're installing this as a domain administrator. Although it won't give you an error message ever if you don't, running as administrator has made all my ODBC connections work properly.
Also, make sure you select "ColdFusion Documentation" during installation, as certain ODBC required files aren't installed unless you also install Documentation.
Frustrating, for sure.
As MX7 is a little dated now, I'll give my take on what seems to work with ColdFusion 8.
I've found that regardless of the environment (be it 2k8 server or earlier), all services and processes run by SYSTEM should have full access. As rmcqarry pointed out, you will need to run as administrator to grant this.
I'm not sure why the installation doesn't do some form of check to make sure that there are sufficient permissions for CF to run properly, but my guess is that in the Adobe development environment, the projects were created with administrator access by default.
I think there needs to be some update to the source code regarding permissions, and perhaps some way to validate installations to ensure all necessary files/processes etc are accessible with admin rights.
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