7z decode file that create by System.IO.Compression.GZipStream failed

Question

A guy write a program in C#, encode it with System.IO.Compression.GZipStream, then does base64 encode it, then save it into XML file.

I grab the Node text data from that XML file and try to decode it

cat custom-config  | base64 --decode > /tmp/custom-config.gz
cd /tmp/ && 7z x custom-config.gz

7z create custom-config and encode some data from original encoded file, but it exit with code 2 (man said it manes Fatal error).

Why 7z could not decode it with exit code 0 ?

Node data:

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

Answer 1

That is not a complete and correct gzip stream. It was not generated properly.