# Launch client jar signature is invalid

**URL:** <https://forum.inductiveautomation.com/t/launch-client-jar-signature-is-invalid/110979>\
**Category:** Ignition\
**Tags:** designer\
**Created:** [September 25, 2025, 5:15pm UTC](https://forum.inductiveautomation.com/t/launch-client-jar-signature-is-invalid/110979 "2025-09-25T17:15:17Z")\
**Posts on this page:** 1\
**Showing post:** 2

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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 25, 2025, 5:45pm UTC](https://forum.inductiveautomation.com/t/launch-client-jar-signature-is-invalid/110979/2 "2025-09-25T17:45:53Z")

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If your 8.1 gateways are older than the signing jar, you need to either upgrade the gateways (so that a signed jar is distributed) or adjust the 8.3 designer launcher to allow unsigned jars (worse for security). See advice in this thread:

> [@Launch client jar invalid](https://forum.inductiveautomation.com/t/launch-client-jar-invalid/109145/7):
>
> Try closing the Designer Launcher first and then change the value to LENIENT

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