# \[Bug\] UDTs not Connecting to OPC Devices

**URL:** <https://forum.inductiveautomation.com/t/bug-udts-not-connecting-to-opc-devices/20638>\
**Category:** Ignition Early Access\
**Created:** [November 7, 2018, 6:54pm UTC](https://forum.inductiveautomation.com/t/bug-udts-not-connecting-to-opc-devices/20638 "2018-11-07T18:54:44Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![p\_hanson](https://avatars.discourse-cdn.com/v4/letter/p/b782af/32.png) [@p\_hanson](https://forum.inductiveautomation.com/u/p_hanson)\
**Post date:** [November 7, 2018, 6:54pm UTC](https://forum.inductiveautomation.com/t/bug-udts-not-connecting-to-opc-devices/20638/1 "2018-11-07T18:54:44Z")

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**Level Config** UDT worked, but **AI\_CLX(Intake Only)** UDT did not. I was showing that using the same methodology, I got different results.

I have two different facilities operating Ignition both at v7.9.9 from VM’s on Windows Server 2008R2. I’m running a test platform of 8.0.0Beta on my local PC with Windows 7 PRO SP1.

I used the Gateway Backup from 7.9.9 of one of our facilities to test on V8.0.0Beta. There are many issues; mainly that none of my tags are communicating with the OPC devices, but I started with the UDT’s not importing properly. I’m assuming I have mistakes elsewhere in configuration of the gateway that is contributing to my missing tag information.

When exporting and import UDT’s from one facility platform (v7.9.9) to the other (also v7.9.9), there were no issues.

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**Author:** ![ggross](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/ggross/32/12668_2.png) [@ggross](https://forum.inductiveautomation.com/u/ggross)\
**Post date:** [November 7, 2018, 7:38pm UTC](https://forum.inductiveautomation.com/t/bug-udts-not-connecting-to-opc-devices/20638/2 "2018-11-07T19:38:08Z")

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I am breaking some of the issues you have noted into new topics to keep things organized.

With your OPC member tag definitions, are do the addresses use Parameters in them? If they do, is there any math done on the parameter like?:  
`{Param1+20}`

If so we are aware of this issue, and it due to the fact that parameters aren’t keeping their data type defined in 7 versions of Ignition.

Also make sure that all your devices are connecting and that none of your OPC UA servers are faulted. The upgrade of the OPC UA module to use Milo will regenerate all certificates and they will need to be approved again on other OPC UA servers.

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**Author:** ![p\_hanson](https://avatars.discourse-cdn.com/v4/letter/p/b782af/32.png) [@p\_hanson](https://forum.inductiveautomation.com/u/p_hanson)\
**Post date:** [November 7, 2018, 10:25pm UTC](https://forum.inductiveautomation.com/t/bug-udts-not-connecting-to-opc-devices/20638/3 "2018-11-07T22:25:53Z")

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No, none of the tag definitions were coded with additional math features.

I uninstalled and reinstalled today. This issues are no longer appearing.

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**Author:** ![ggross](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/ggross/32/12668_2.png) [@ggross](https://forum.inductiveautomation.com/u/ggross)\
**Post date:** [November 7, 2018, 11:12pm UTC](https://forum.inductiveautomation.com/t/bug-udts-not-connecting-to-opc-devices/20638/4 "2018-11-07T23:12:43Z")

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Closed on November 7, 2018, 11:12pm UTC