Dts packages run on the client so you will find that if you are referencing the c: drive to locate the ini file, the c: drive will be the client NOT the server.
That's why running the package on the server works OK.
Choices are:
Replicate the ini file on the client that you are running the package from.
Or, map a network drive to the location of the ini file. This is more risky as everyone needs to have the same drives mapped.
Or, create a dfs name to the location of the file. OK as long as you never change the dfs names.
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