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What Version of Allen Bradley Firmware is compatible with the IGS Driver?

See GE KB Article:

https://digitalsupport.ge.com/s/article/IGS-OPC-Server-supported-firmware-for-Allen-Bradley-ControlLogix

Allen Bradley Firmware Compatibility

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IGS version 7.614 supports up to version 34 of ControlLogix firmware
IGS version 7.615 supports up to version 34 of ControlLogix firmware

IGS version 7.616 supports up to version 35 of ControlLogix firmware

Note: PTC (Kepware) has confirmed the following specific Firmware versions are NOT supported at all with the IGS:
20.14
20.19 
20.57
20.58 
33.12

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