Compress-Archive Not Working?

[johnmsch]

I'm running Powershell version 5.1.17763.4974 on a server with Windows Server 2019 Datacenter v10.

Been using PS for years but trying Compress-Archive for the first time.

Tried building a script which didn't work.  When executing the script, it immediately goes right back to the PS prompt and nothing happens.

Trying to execute a simple command directly with something like this: 

Compress-Archive -Path 'D:\abc\*.*'  -DestinationPath 'D:\xyz\abc.zip'

Same thing happens.  Goes immediately back to the PS prompt.

I'm running PS as administrator.

What am I missing?

[#2]

@johnmsch 

Hi, John.

Have a look at examples four and five, as you've specified the format (i.e. *.*) that explicitly only adds files from d:\abc. Subfolders and files from those subfolders will not be added.

If there's files in d:\abc then something would appear to be wrong. If there's no files but there are subfolders then what you're observing is expected behaviour, and you should change *.* simply to *, as per example four.

• Compress-Archive (Microsoft.PowerShell.Archive) - PowerShell | Microsoft Learn

Also note that Compress-Archive has limitations - when compared to the underlying .NET class upon which it's based, which I spoke to in another thread:

• Re: Macos compress can't zip a folder.but can zip a file - Microsoft Community Hub

Cheers,

Lain

[#3]

Thank you @LainRobertson 

I had read through that article and completely missed the obvious answer:
This: Compress-Archive -Path 'D:\abc\' -DestinationPath 'D:\xyz\abc.zip'
Instead of this: Compress-Archive -Path 'D:\abc\*.*' -DestinationPath 'D:\xyz\abc.zip'

Is working perfectly.
In fact, the folder D:\abc is indeed empty, but there are multiple folders on the next level.

If I may, I have two more questions.
I believe I read somewhere that using this compression method is limited to 2gb file sizes?
Is there a way to remove files from a compressed file leaving everything else in tact?

Thanks again for your quick answer and that excellent article!

[#4]

@johnmsch 

Hey, John.

Yes, you certainly can manipulate an archive, however, you have to do so from .NET. Here's a very basic example, which you can easily extend as it's a pretty simple set of classes to work with.

Example

# Add the required .NET library reference.
Add-Type -AssemblyName "System.IO.Compression.FileSystem";

# Open the Zip file.
$Archive = [System.IO.Compression.ZipFile]::Open("<full path to your Zip file>", [System.IO.Compression.ZipArchiveMode]::Update);

# Delete the first entry.
$Archive.Entries[0].Delete();

# Finish up properly by disposing the $Archive object.
$Archive.Dispose();

In a real-world context, you'd most likely enumerate the Entries collection and make smarter decisions based on file size, type, etc.

References

• ZipFile Class (System.IO.Compression) | Microsoft Learn
• ZipArchive Class (System.IO.Compression) | Microsoft Learn
• ZipArchiveEntry Class (System.IO.Compression) | Microsoft Learn

Cheers,

Lain

[#5]

Thanks again for all you help @LainRobertson 

Hope you have a wonderful weekend!