# \[IGN-15623\]Unable to create new class error

**URL:** <https://forum.inductiveautomation.com/t/ign-15623-unable-to-create-new-class-error/114301>\
**Category:** Ignition\
**Tags:** vision\
**Created:** [March 3, 2026, 7:50pm UTC](https://forum.inductiveautomation.com/t/ign-15623-unable-to-create-new-class-error/114301 "2026-03-03T19:50:57Z")\
**Posts on this page:** 4\
**Page:** 1

<div class="post-metadata">

**Author:** ![aaaa](https://avatars.discourse-cdn.com/v4/letter/a/eb8c5e/32.png) [@aaaa](https://forum.inductiveautomation.com/u/aaaa)\
**Post date:** [March 3, 2026, 7:50pm UTC](https://forum.inductiveautomation.com/t/ign-15623-unable-to-create-new-class-error/114301/1 "2026-03-03T19:50:57Z")

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I’m getting this error when I create a template instance. Nothing is special about this template or instance compared to other ones I’ve created so I’m confused

```python

java.lang.ClassCastException: Unable to create new class com.inductiveautomation.ignition.common.model.values.QualityCode. com.inductiveautomation.ignition.common.model.values.QualityCode
at com.inductiveautomation.ignition.common.TypeUtilities$DefaultClassInitializer.createNew(TypeUtilities.java:2217)
at com.inductiveautomation.ignition.common.TypeUtilities.getInitValueForClass(TypeUtilities.java:2157)
at com.inductiveautomation.factorypmi.application.binding.AbstractPropertyAdapter.setQValue(AbstractPropertyAdapter.java:217)
at com.inductiveautomation.factorypmi.application.binding.SimpleBoundTagAdapter.setQValue(SimpleBoundTagAdapter.java:259)
at com.inductiveautomation.factorypmi.application.binding.AbstractPropertyAdapter.updateValue(AbstractPropertyAdapter.java:269)
at com.inductiveautomation.factorypmi.application.binding.SimpleBoundTagAdapter.notifyTagChanged(SimpleBoundTagAdapter.java:518)
at com.inductiveautomation.factorypmi.application.binding.SimpleBoundTagAdapter.tagChanged(SimpleBoundTagAdapter.java:506)
at com.inductiveautomation.ignition.client.tags.impl.ClientTagSubscriptionManager$ListenerDeliveryManager.edtDeliver(ClientTagSubscriptionManager.java:608)
at java.desktop/java.awt.event.InvocationEvent.dispatch(Unknown Source)
at java.desktop/java.awt.EventQueue.dispatchEventImpl(Unknown Source)
at java.desktop/java.awt.EventQueue$4.run(Unknown Source)
at java.desktop/java.awt.EventQueue$4.run(Unknown Source)
at java.base/java.security.AccessController.doPrivileged(Unknown Source)
at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(Unknown Source)
at java.desktop/java.awt.EventQueue.dispatchEvent(Unknown Source)
at com.inductiveautomation.snap.swing.RibsEventQueue.dispatchEvent(RibsEventQueue.java:99)
at java.desktop/java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)
at java.desktop/java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)
at java.desktop/java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
at java.desktop/java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.desktop/java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.desktop/java.awt.EventDispatchThread.run(Unknown Source)

Ignition v8.1.45 (b2025010709)
Java: Azul Systems, Inc. 17.0.13

```

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<div class="post-metadata">

**Author:** ![pturmel](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/pturmel/32/3295_2.png) [@pturmel](https://forum.inductiveautomation.com/u/pturmel)\
**Post date:** [March 3, 2026, 7:54pm UTC](https://forum.inductiveautomation.com/t/ign-15623-unable-to-create-new-class-error/114301/2 "2026-03-03T19:54:44Z")

</div>

That backtrace is entirely within IA code. You should open a support ticket. This looks like a real bug. (Triggered by some odd init value corner case, presumably.)

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<div class="post-metadata">

**Author:** ![aaaa](https://avatars.discourse-cdn.com/v4/letter/a/eb8c5e/32.png) [@aaaa](https://forum.inductiveautomation.com/u/aaaa)\
**Post date:** [March 3, 2026, 7:59pm UTC](https://forum.inductiveautomation.com/t/ign-15623-unable-to-create-new-class-error/114301/3 "2026-03-03T19:59:01Z")

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I found the bug. The quality property for sth was linked to a tag incorrectly

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<div class="post-metadata">

**Author:** ![paul-griffith](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/paul-griffith/32/37249_2.png) [@paul-griffith](https://forum.inductiveautomation.com/u/paul-griffith)\
**Post date:** [March 4, 2026, 12:26am UTC](https://forum.inductiveautomation.com/t/ign-15623-unable-to-create-new-class-error/114301/4 "2026-03-04T00:26:36Z")

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Though you worked around it OP, I filed an internal ticket so we'd get this fixed.

I can't tell exactly what you did, but I can reproduce the same stacktrace by just adding an expression binding on the Quality ( **not** the Data Quality) field that returns something that isn't a `QualityCode`.  
Internally, that's triggering a class cast exception (because e.g. the literal value `0` is not a valid QualityCode) but in the process of handling that CCE we're throwing a different class cast exception, which is interrupting the standard error handling flow for the binding.