# C# Elasticsearch 8.0.3+ 400 Bad Request media\_type\_header\_exception

**URL:** <https://discuss.elastic.co/t/c-elasticsearch-8-0-3-400-bad-request-media-type-header-exception/322816>\
**Category:** Elasticsearch\
**Tags:** docker, language-clients\
**Created:** [January 10, 2023, 9:59am UTC](https://discuss.elastic.co/t/c-elasticsearch-8-0-3-400-bad-request-media-type-header-exception/322816 "2023-01-10T09:59:12Z")\
**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:** [January 11, 2023, 3:14pm UTC](https://discuss.elastic.co/t/c-elasticsearch-8-0-3-400-bad-request-media-type-header-exception/322816/2 "2023-01-11T15:14:26Z")

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Hi, @KoalaBear.

If this works locally but not when deployed, possibly something in the way it is deployed is breaking the logic which loads the version from our assembly info. We[saw this for a user](https://discuss.elastic.co/t/nest-product-check-call-fails-every-time/306348/2) who was creating a single DLL causing the version lookup to fail. Are you packaging your application in an unusual way that might cause a similar behaviour?

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