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unsupported compression method 0x62

Apr 24, 2009 at 1:21 PM
Edited Apr 24, 2009 at 2:08 PM
getting an error on unzipping a file created by winzip 11.0 with the default zip method of "Optimize for maximum compressions (use best method for each file type)" , works fine if I choose "Legacy compression(Zip 2.0 compatible)" however .... and well, while I could ask the user which compression button to check, I'll get a lot of flack ( people moan about the simplest things ) .... btw sharpziplib unzips the same file with no problem, but thats much more difficult to do what I want to ... which as an addendum if I get this issue solved... the user will zip a file on their pc(using winzip which is installed on all machines) then will upload the zip file to a location of my choosing wher I need to extract the contents(which consists of an html document I will have to rename btw, and a subfolder of files that are referenced by the html file relatively) and change the directory structure to what I need it to be at the new location ...any help?
btww, I'm doing this with a web interface which is why ,afaik, they have to use winzip to zip the html file and the subfolder..then  I use the file upload control to move the zip file and unzip it at the destination

edit: finally figured out how to look in the zipfile and I believe this smay help?
"compression method (98): ppmd encoding"
I deleted all files in the zip except the first one, this is the only compression method mentioned(previously I saw method (09) and (00)
edit 2: also fails on method (0x09) ... am I doing something wrong?
edit3: used th legacy compression option, then compression method (0x08) is used and unzips fine....


Apr 24, 2009 at 1:28 PM
Edited Apr 24, 2009 at 1:32 PM
by the way heres the code,  I am using, version 1.8(figured Id try it since 1.7 was getting the error, but same in 1.8)
havent implemented any of the changing the dir structure yet, straight from the examples, just hardcoded the paths for now for testing



Dim OverwriteAnyExistingFiles As Boolean = True

Dim basepath As String

asepath = "\\cmiweb1\development$\plab\"

Dim ZipToUnpack As String = basepath

Dim UnpackDirectory As String = "\\cmiweb1\development$\plab"

StatusMessage.Text = String.Format("Extracting file {0} to {1}", ZipToUnpack, UnpackDirectory)

Using zip1 As ZipFile = ZipFile.Read(ZipToUnpack)

'AddHandler zip1.ExtractProgress, AddressOf MyExtractProgess

Dim e As ZipEntry

' here, we extract every entry, but we could extract conditionally,  ' based on entry name, size, date, checkbox status, etc.

For Each e In zip1

Dim ex As ExtractExistingFileAction = ExtractExistingFileAction.OverwriteSilently

 e.Extract(UnpackDirectory, ex)


End Using

End Sub

Apr 28, 2009 at 7:33 PM

DotNetZip supports the DEFLATE compression algorithm.  DotNetZip does not support PPMd (0x98) or DEFLATE64 (0x09).