The only way you can get an error is like is if the file you're giving SharpCompress is a bad or invalid archive.
Since you're saying that you can hardcore the path and make it work, I can only assume there's not anything wrong with SharpCompress.
The path in your second case has to be wrong. I can't help anything beyond that.
Since you're saying that you can hardcore the path and make it work, I can only assume there's not anything wrong with SharpCompress.
The path in your second case has to be wrong. I can't help anything beyond that.