# OPC UA Error: Expected data is unavailable for the requested time range due to an un-mounted volume

**URL:** <https://forum.inductiveautomation.com/t/opc-ua-error-expected-data-is-unavailable-for-the-requested-time-range-due-to-an-un-mounted-volume/100881>\
**Category:** General Discussion\
**Created:** [January 14, 2025, 7:07pm UTC](https://forum.inductiveautomation.com/t/opc-ua-error-expected-data-is-unavailable-for-the-requested-time-range-due-to-an-un-mounted-volume/100881 "2025-01-14T19:07:18Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![Michael\_Crawley](https://avatars.discourse-cdn.com/v4/letter/m/f05b48/32.png) [@Michael\_Crawley](https://forum.inductiveautomation.com/u/Michael_Crawley)\
**Post date:** [January 14, 2025, 7:07pm UTC](https://forum.inductiveautomation.com/t/opc-ua-error-expected-data-is-unavailable-for-the-requested-time-range-due-to-an-un-mounted-volume/100881/1 "2025-01-14T19:07:18Z")

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I am using Kepare to create an OPC UA Connection to a plastics press. I know very little about OPC UA outside of the configuation. Far as understand it to make a connection you simply open some ports and pretty much browse to the the tags you want. I posted a photo the error pretty much showing the process.

So I can select tags when I browse to the PLC. I select the ones I want then I click OK. To check my tags I run the OPC QC and I get the error noted. The actual error is "Expected data is unavailable for the requested time range due to an un-mounted volume". If anyone could provide some insight it to what this errir I would really appreciate it." I don't know if it is client side or a server side issue.

The Error Mean : "BadDataUnavailable" that is not much help to me.

I would like to know, in human terms, what the error is and what could be causing it. I would really apprcate any insight you could provide.

 ![Error](https://us1.discourse-cdn.com/inductiveautomation/original/3X/8/e/8e1a624ca85dbfd082786d0f0be2f2f046774bb9.png)

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**Author:** ![Kevin.Herron](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/kevin.herron/32/7259_2.png) [@Kevin.Herron](https://forum.inductiveautomation.com/u/Kevin.Herron)\
**Post date:** [January 14, 2025, 7:24pm UTC](https://forum.inductiveautomation.com/t/opc-ua-error-expected-data-is-unavailable-for-the-requested-time-range-due-to-an-un-mounted-volume/100881/2 "2025-01-14T19:24:23Z")

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You _probably_ need to get support from the vendor of this PLC / Server.

I can't say for sure since neither of these are Ignition, but it looks like the Kepware client is trying to create Monitored Items and the Server is responding with `Bad_DataUnavailable`.

It has a goofy description because this isn't really a StatusCode you are supposed to use at the operation or service level for Monitored Items; it's defined by part 11 for use with history services. A developer who wasn't paying much attention might use it anyway because its name "sounds" relatively appropriate to them (ignoring the description).

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**Author:** ![Michael\_Crawley](https://avatars.discourse-cdn.com/v4/letter/m/f05b48/32.png) [@Michael\_Crawley](https://forum.inductiveautomation.com/u/Michael_Crawley)\
**Post date:** [January 14, 2025, 7:33pm UTC](https://forum.inductiveautomation.com/t/opc-ua-error-expected-data-is-unavailable-for-the-requested-time-range-due-to-an-un-mounted-volume/100881/3 "2025-01-14T19:33:35Z")

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Thanks Kevin - It seems to me the server has no idea what it is looking at. So it throws the message. So it sees it but can't translate it. That was my thought.