*** ... /config.txt]
could not be opened for writing! ***
The error message looks to say it all. It looks like improper permissions are set for the file sited.
I don't know how you go about changing that on a Windows? server. Either check server's documentation or maybe someone else can suggest a way... although you didn't state which Windows? server you're dealing with. I believe there is more than one type... but then again, I don't so windows.
Dan O.
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