# Designer error - Cannot create PyString with non-byte value

**URL:** <https://forum.inductiveautomation.com/t/designer-error-cannot-create-pystring-with-non-byte-value/50795>\
**Category:** Ignition\
**Created:** [September 9, 2021, 8:16pm UTC](https://forum.inductiveautomation.com/t/designer-error-cannot-create-pystring-with-non-byte-value/50795 "2021-09-09T20:16:13Z")\
**Posts on this page:** 1\
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**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:** [September 10, 2021, 2:40pm UTC](https://forum.inductiveautomation.com/t/designer-error-cannot-create-pystring-with-non-byte-value/50795/4 "2021-09-10T14:40:24Z")

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In the context the designer launcher is creating the new Designer instance, there’s an environment variable set with a non-ASCII name. That’s pretty unusual, especially since you’re encountering this on different machines; maybe it’s something being provided by your AD domain or other Windows setup?  
If the Ubuntu install has a desktop environment, you could try launching a designer there. You can see the names and values of the default environment variables on Windows pretty easily:  
[https://www.architectryan.com/2018/08/31/how-to-change-environment-variables-on-windows-10/](https://www.architectryan.com/2018/08/31/how-to-change-environment-variables-on-windows-10/)

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