I got the above error upon attempting to install Oracle Data Provider for .NET (ODP.NET) and ODAC Software, Release 10.1.0.4.0 (http://www.oracle.com/technology/software/tech/windows/ole_db/htdocs/utilsoft.htm) on Windows XP.
Here is a chunk from the log: Calling Action generalActions10.1.0.3.0 setenv
name = path
value = C:\oracle\product\10.1.0\Client_2\jre\1.4.2\bin
append = null
replace = null
Exception thrown from action: setenv
Exception Name: ValueTooLongException
Exception String: The value of the enviroment variable path is more than 1023 characters. This value cannot be set.
Exception Severity: 0
*** Cancel Dialog: ***
User Selected: Stop installation of all products.
Exception handling set to prompt user with options to Retry Ignore
User Choice: User selected to stop installation of all components.
The value of the enviroment variable path is more than 1023 characters. This value cannot be set.
I've looked at my PATH variable, it is already greater than 1023 characters.
yes, you are pretty much stuck, but one thing you could try is to tighten up the directory names (I suppose you'll have to uninstall / reinstall a mess of stuff), for example instead of installing something into c:\program files\Microsoft\Microsoft SQL SERVER version 7 - make it c:\SQLS7. A real pain to implement, but if you have to...
I managed to resolve this problem by creating a new environment variable "PATH2" and then assigning the value of the existing path variable to it. Then delete whatever is in the path variable and put %PATH2% as the new value. This worked on my laptop where I have both the DB and App Server installed.