DLL file does not exist error...... thoughts??

Aug 3, 2012 at 1:25 PM


I just downloaded the latest recommended version (Aug 26 2010 version) to use in my .Net 4.0 (VS 2010) application.  I added the SevenZipSharp.dll as a new Reference in my VS 2010 project.  In my C# class I added the following:

using SevenZip;


public void HandleRARFile(string filePath, string directory) {

    using (SevenZipExtractor extr = new SevenZipExtractor(filePath)) {





When I ran the code, however, I got the following error:

SevenZip.SevenZipLibraryException: Can not load 7-zip library or internal COM error! Message: DLL file does not exist.

Not sure what I am missing with this.  Is there another DLL I need that I don't know about?


Thanks for any thoughts - Peter

Aug 31, 2012 at 1:15 PM

Wow, I have to say that any help on this forum is virtually non-existent.  In any case, wanted to post what I found in solving the issue on this post in case someone else runs into this.  While there seems to be ZERO documentation or "how to" information, I was able to piece together what was happening through pieces of old posts.  What I found was that you need to download the SevenZipSharp.dll and add that as a reference to your .Net VS (I am using VS 2010) project.  Then, in your code, you need to do a SevenZipExtractor.SetLibraryPath(pathToThe7z.dll) where the path you give it is to the 7z.dll (or 7z64.dll) file.  The "DLL file does not exist" error I got was due to not using the SetLibraryPath, and then my mistake was setting the path to my SevenZipSharp.dll file, which produced a "library is invalid" error.  Once I put the path to a copy of the 7z.dll file, I didn't get any error.  It would have been EXTREMELY helpful if there was something that explained that this is what was needed.

So....... I now have gotten past the initial issues but now find that my extractor.ExtractArchive(directory) call does not do anything (ie. files are not extracted to the directory). 

Aug 31, 2012 at 10:56 PM

Here is a little article to get you started:


If you need help converting this into vb.net use this website: