---
title: "UnknownTagException Class"
canonical: https://www.graphicsmill.com/docs/gm/T_Aurigma_GraphicsMill_Drawing_UnknownTagException.htm
archived: false
applies_to:
  - product: "Graphics Mill"
    versions: ["12.1", "6.x-12.x (may differ)"]
    entity_id: "https://www.graphicsmill.com/#software-application"
---

# UnknownTagException Class

**Applies to:** Graphics Mill 12.1, 6.x-12.x (may differ)
 
Represents the error that occurs when there is an unknown tag in formatted text.
 
**Namespace:** [Aurigma.GraphicsMill.Drawing](https://www.graphicsmill.com/docs/gm/N_Aurigma_GraphicsMill_Drawing.htm.md)
 **Assembly:** Aurigma.GraphicsMill (in Aurigma.GraphicsMill.dll)
 
## Syntax
  
```csharp
public class UnknownTagException : GMException
```
 
## Inheritance Hierarchy
  
- System.Object
    - System.Exception
        - [Aurigma.GraphicsMill.GMException](https://www.graphicsmill.com/docs/gm/T_Aurigma_GraphicsMill_GMException.htm.md)
            - Aurigma.GraphicsMill.Drawing.UnknownTagException
 
## Thread Safety
 Static members of this type are not safe for multi-threaded operations. Instance members of this type are not safe for multi-threaded operations.
   
## See Also

### Reference

- [UnknownTagException Members](https://www.graphicsmill.com/docs/gm/AllMembers_T_Aurigma_GraphicsMill_Drawing_UnknownTagException.htm.md)
- [Aurigma.GraphicsMill.Drawing Namespace](https://www.graphicsmill.com/docs/gm/N_Aurigma_GraphicsMill_Drawing.htm.md)

### Manual

- [Formatted Text](https://www.graphicsmill.com/docs/gm/advanced-formatted-text.htm.md)