The error:
Ionic.Zlib.ZlibException: Bad state (invalid block type)
during Build Deployment Structure → ExportWidgets
means:
Studio Pro is failing while unzipping the widget package (.mpk)
This is not a runtime issue and not related to your app logic.
It indicates a corrupted or incompatible widget package.
In Mendix 11.x, widget packaging changed (new web modeler structure + updated build pipeline).
Some older or incorrectly packaged widgets fail during unzip.
Most common causes:
widgets folderThe Zlib “invalid block type” specifically means the ZIP content is invalid or corrupted.
Then manually delete:
<ProjectFolder>\widgets\ <ProjectFolder>\deployment\ <ProjectFolder>\node_modules\
Delete:
C:\Users\<user>\AppData\Local\Mendix\
Restart Studio Pro.
Download again from Marketplace
Ensure you are using the version explicitly marked compatible with Mendix 11.x
If not officially compatible with 11.7 → it will break build.
Then it is a widget packaging issue, and the vendor (Aiden) must repackage it for Mendix 11 build structure.
This error is not fixable at project level if the MPK itself is invalid.
This is a corrupted or incompatible widget archive issue during build export in Mendix 11.7.
Clean project folders + reinstall widget usually resolves it.
If not, the widget must be updated by the provider for Mendix 11 compatibility.
There is currently an issue with 11.6.3 and 11.7.0 and downloading content from the Marketplace. Several of my widgets cannot be downloaded using these Mendix versions. Also platform supported Switch and Pop-up menu are affected by this issue. I have ticket 270889 open for this. 11.6.2 can download these widgets just fine.
Studio Pro 11.6.4 and 11.8.0 have been released which fixes the issue.
Did you check out this thread? If not, try this solution you mentioned in the thread. When your issue persists, I'll help you again.
Then I'll wait to update till this is fixed.
Thanks, I'll give it a try en keep you posted. Kind regards Peter
I did some of the steps as mentioned above:: delete deployment AND
downloaded (not via Studio pro) like Marcel is mentioning:
"If you need a workaround: Go to the Marketplace in the browser, search the item and go to its releases tab. There you can download the widget .mpk and then move it into the widgets folder manually."
and it seems fine.
Thanks and kind regards
Peter