# OPC server tags on error, Can UDT offset create problem on OPC connection?

**URL:** <https://forum.inductiveautomation.com/t/opc-server-tags-on-error-can-udt-offset-create-problem-on-opc-connection/47126>\
**Category:** Ignition\
**Tags:** ignition80, perspective\
**Created:** [May 26, 2021, 8:20am UTC](https://forum.inductiveautomation.com/t/opc-server-tags-on-error-can-udt-offset-create-problem-on-opc-connection/47126 "2021-05-26T08:20:29Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![berkay.cinar](https://avatars.discourse-cdn.com/v4/letter/b/b9bd4f/32.png) [@berkay.cinar](https://forum.inductiveautomation.com/u/berkay.cinar)\
**Post date:** [May 26, 2021, 8:20am UTC](https://forum.inductiveautomation.com/t/opc-server-tags-on-error-can-udt-offset-create-problem-on-opc-connection/47126/1 "2021-05-26T08:20:29Z")

</div>

Hello everybody,

I have a perspective project I am working on. I suddenly got error on all my tags. I have 4 device all S7-300 connected to gateway. Devices looks connected I can ping them succesfully. An I was receiving the tag values also but for some reason I started to get this error on all my tags. Below the device logs;

 ![image](https://us1.discourse-cdn.com/inductiveautomation/original/3X/3/8/38a75438ffe372ed02958c83d980fe54d7deb694.png)

In the tag diagnostic it says bad.

I chekced the gateway connection OPC connection, PLC configuration allowing OPC connection they look fine. In the tag configurations I use lots of UDT , I saw a post about UDT offset values making problems. Could this be the reason I suddenly started to have problem on tags? I have offset values in most of my UDT tags. Usually like this;

![image](https://us1.discourse-cdn.com/inductiveautomation/original/3X/2/a/2a3ee790d1021ff669a55ce1cb4ab28ee19fed83.png)

I also had some mathematical calculation in the offset part I deleted those in hope maybe that fixes but still same. Any idea?

BR