# Opc-ua write failure

**URL:** <https://forum.inductiveautomation.com/t/opc-ua-write-failure/29045>\
**Category:** Ignition\
**Created:** [October 12, 2019, 9:44am UTC](https://forum.inductiveautomation.com/t/opc-ua-write-failure/29045 "2019-10-12T09:44:27Z")\
**Posts on this page:** 3\
**Page:** 1

<div class="post-metadata">

**Author:** ![claudio](https://avatars.discourse-cdn.com/v4/letter/c/7cd45c/32.png) [@claudio](https://forum.inductiveautomation.com/u/claudio)\
**Post date:** [October 12, 2019, 9:44am UTC](https://forum.inductiveautomation.com/t/opc-ua-write-failure/29045/1 "2019-10-12T09:44:28Z")

</div>

Hello,  
I connected my Ignition to an OPC-UA Server.  
I can read and write every available nodes, I can write string nodes, but I can’t write a single component of a integer array.  
When i try to change for example the first component of this array tag I receive the following message.  
If I try with another client, it works fine.  
I’m using Ignition 7.9.8 (b2018060714)  
Can you help me?  
Thank you

![opc-ua_error](https://us1.discourse-cdn.com/inductiveautomation/original/2X/d/d7b012031aa41df33e8a72309369dea1a72d1712.jpeg)

---

<div class="post-metadata">

**Author:** ![Sanderd17](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/sanderd17/32/8735_2.png) [@Sanderd17](https://forum.inductiveautomation.com/u/Sanderd17)\
**Post date:** [October 14, 2019, 8:24am UTC](https://forum.inductiveautomation.com/t/opc-ua-write-failure/29045/2 "2019-10-14T08:24:28Z")

</div>

As far as I know, writing to arrays isn’t supported. You can often read the array into separate variables, and write those. But it depends on the version of the OPC-UA protocol in use.

---

<div class="post-metadata">

**Author:** ![claudio](https://avatars.discourse-cdn.com/v4/letter/c/7cd45c/32.png) [@claudio](https://forum.inductiveautomation.com/u/claudio)\
**Post date:** [October 14, 2019, 3:14pm UTC](https://forum.inductiveautomation.com/t/opc-ua-write-failure/29045/3 "2019-10-14T15:14:36Z")

</div>

It seems that you can’t write single components!  
it looks I can write the whole array.  
So I need to compose my temp tag array and then write to the OPC tag with a system.tag.write(OPC\_TAG\_ARRAY, TEMP\_TAG\_ARRAY.value) at once

Anyway, many thanks  
Claudio