# NEST product check call fails every time

**URL:** <https://discuss.elastic.co/t/nest-product-check-call-fails-every-time/306348>\
**Category:** Elasticsearch\
**Tags:** docker, language-clients\
**Created:** [June 3, 2022, 5:18pm UTC](https://discuss.elastic.co/t/nest-product-check-call-fails-every-time/306348 "2022-06-03T17:18:57Z")\
**Posts on this page:** 1\
**Showing post:** 2

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**Author:** ![stevejgordon](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/stevejgordon/32/80912_2.png) [@stevejgordon](https://discuss.elastic.co/u/stevejgordon)\
**Post date:** [June 4, 2022, 4:46pm UTC](https://discuss.elastic.co/t/nest-product-check-call-fails-every-time/306348/2 "2022-06-04T16:46:47Z")

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Hi @Kristinn_Vikar,

I think this likely is due to the invalid `compatible-with` value. Looking at your capture, the `x-elastic-client-meta` header is also reflecting unexpected version for `es=` and `t=` which should match the version of the client you have referenced.

I've just had a quick look to see if I can reproduce this. I created a very simple client app which I added to an image which runs it based on the Microsoft `mcr.microsoft.com/dotnet/runtime:6.0-alpine` image. When I ran it and captured the headers it sent, they appeared as expected:

 ![image](https://us1.discourse-cdn.com/elastic/original/3X/e/5/e5b56ad965309a9ea60d52add3d194ae16794ea4.png)

Internally the client uses reflection to grab version information on the assembly containing the `IElasticLowLevelClient` type; so essentially:

```auto
FileVersionInfo.GetVersionInfo(typeof(IElasticLowLevelClient).GetTypeInfo().Assembly.Location)?.ProductVersion;

```

This is presumably failing to return a value in your environment. Could you try adding some code to your app code and log out the values to see what you get. I want to first check if for some reason the version information is not retrieved in your environment.

```auto
var location = typeof(IElasticLowLevelClient).GetTypeInfo().Assembly.Location;
var version = FileVersionInfo.GetVersionInfo(location)?.ProductVersion;

Console.WriteLine(location); // or send to a logged etc.
Console.WriteLine(version); // or send to a logged etc.

```

Can you please confirm the base image and label for your client app Docker image. If possible, it would be great to see your Dockerfile for your image.

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_[View the full topic](https://discuss.elastic.co/t/nest-product-check-call-fails-every-time/306348)._