The filename 'filename' already exists VB .NET

Question

I want to extract archive. But the problem is, when the code runs, it throws the exception below:

System.IO.IOException: 'The file 'filename' already exists.'

Here are the code

File.WriteAllBytes(String_TempDir & "\rzip.zip", My.Resources.Resszip) 'I wrote the file from my application resources
Compression.ZipFile.ExtractToDirectory(String_TempDir & "\rzip.zip", String_TempDir) 'This line throws the exception
File.Delete(String_TempDir & "\rzip.zip")

I saw nothing(no file) before that code executed...

After the code executed, It throws the exception, but, my archived file has been extracted.

I used Try statement to distinguish the exception but it's still throwing that exception...

Try
    Compression.ZipFile.ExtractToDirectory(String_TempDir & "\rzip.zip", String_TempDir)
Catch ex As IOException
    'That's it.
End Try

The String_TempDir is a string which I assign it with:

'global declaration:
Dim folder As String = Path.Combine(Path.GetTempPath, Path.GetRandomFileName)
'End of global declaration

Public Function GetTempDir() As String

    Do While Directory.Exists(folder) Or File.Exists(folder)

        folder = Path.Combine(Path.GetTempPath, Path.GetRandomFileName)

    Loop

    Return folder

End Function

'Form loads
Directory.CreateDirectory(folder)
String_TempDir = folder

In the [docs](https://msdn.microsoft.com/en-us/library/system.io.compression.zipfileextensions.extracttodirectory(v=vs.110).aspx) there are many causes listed under the IOException case. Check if one of them applies — Steve, Jun 15 '17 at 07:30
Possible duplicate of [System.IO.Compression and ZipFile - extract and overwrite](https://stackoverflow.com/questions/15464740/system-io-compression-and-zipfile-extract-and-overwrite) — Pikoh, Jun 15 '17 at 07:33

score 0 · Accepted Answer · answered Jun 15 '17 at 07:55

Just guessing, but it could be that you are putting the Zip file into the same directory you are extracting to. Try extracting to a subdirectory of your temp directory. e.g.

Compression.ZipFile.ExtractToDirectory(String_TempDir & "\rzip.zip", String_TempDir & "\extracted")

The MSDN article on ExtractToDirectory says the following (emphasis mine):

This method creates the specified directory and all subdirectories. The destination directory cannot already exist. Exceptions related to validating the paths in the destinationDirectoryName or sourceArchiveFileName parameters are thrown before extraction. Otherwise, if an error occurs during extraction, the archive remains partially extracted. Each extracted file has the same relative path to the directory specified by destinationDirectoryName as its source entry has to the root of the archive.

score 0 · Answer 2 · answered Jun 15 '17 at 09:39

Have you also checked that the Zip file doesn't contain any duplicate names? If it was compressed on Linux, it might have both Filename and filename inside it, and that might cause this error. Especially since you say that it doesn't contain any files at first and that it seems that it succeeds in decompressing it.

Somewhat similar question here, but with 7-Zip

The filename 'filename' already exists VB .NET

2 Answers2