iLogic code to zip files suddenly stopped working

[b.graaf]

Hi!

I have an iLogic code which generate several stepfiles and add them into a new created compressed folder (ZIP).

I am using it in several Inventor versions and we are now on the latest Inventor professional 2025.

I have used this iLogic rule about a year ago for the last time and now it suddenly does not work anymore!

I did not change anything in the code.

Is there something changed within iLogic, or maybe in .net?

I am using this line:

System.IO.Compression.ZipFile.CreateFromDirectory(_export_Location, _ZipFileName)

But get this message:

Error on Line 190 : 'ZipFile' is not a member of 'System.IO.Compression'.

Does somebody has any idea?

[bradeneuropeArthur]

Have you add the reference 

To use the ZipFile class in a .NET Framework app, you must add a reference to the System.IO.Compression.FileSystem assembly in your project. For information on how to add a reference to your project 

[b.graaf]

Hi Arthur,

Thank you for your reply.

Just to be clear, we are using this iLogic rule for about 4 years without any problems! We did not change anything to the code and now suddenly, it does not work anymore. 

In the code there are the next two refferences, and the one you have mentioned is one of them:

AddReference "System.IO.Compression"
AddReference "System.IO.Compression.FileSystem"

So I am wondering, if it has to do with some change in for example dot.net or something?

[JelteDeJong · Accepted solution]

There was a big change in Inventor 2025. We went from .Net Framework 4.8 to .Net Core 8. Some things might not work any more. (Officially addins need to migrate to .Net core to work for that reason.) Anyway, you might try to add this to the top of your rule:

AddReference "C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\.NETFramework\v4.8\System.IO.Compression.FileSystem.dll"

[b.graaf]

That did the trick, thanx!