# Startup error ("already been instantiated") using Full Framework Elastic APM Agent

**URL:** <https://discuss.elastic.co/t/startup-error-already-been-instantiated-using-full-framework-elastic-apm-agent/207707>\
**Category:** APM\
**Tags:** dotnet\
**Created:** [November 13, 2019, 12:44pm UTC](https://discuss.elastic.co/t/startup-error-already-been-instantiated-using-full-framework-elastic-apm-agent/207707 "2019-11-13T12:44:33Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![NeoX](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/neox/32/47249_2.png) [@NeoX](https://discuss.elastic.co/u/NeoX)\
**Post date:** [November 13, 2019, 12:44pm UTC](https://discuss.elastic.co/t/startup-error-already-been-instantiated-using-full-framework-elastic-apm-agent/207707/1 "2019-11-13T12:44:33Z")

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**APM Agent language and version** : Full Framework 1.1.2

**Browser version** : Chrome 78.0.3904.97

**Original install method** : From source

**Description of the problem including expected versus actual behavior.** :  
I have followed the configuration instructions [here](https://www.elastic.co/guide/en/apm/agent/dotnet/current/setup.html#setup-asp-net), but I get the following exception on startup:

> The singleton APM agent has already been instantiated and can no longer be configured

I've [raised an issue on GitHub already](https://github.com/elastic/apm-agent-dotnet/issues/596) (including stack trace) as it appears to be a bug (based on debugging the source code), but I would appreciate a workaround or indeed a pointer in the right direction if I am doing something wrong.

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**Author:** ![Sergey\_Kleyman](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/sergey_kleyman/32/39333_2.png) [@Sergey\_Kleyman](https://discuss.elastic.co/u/Sergey_Kleyman)\
**Post date:** [November 13, 2019, 1:40pm UTC](https://discuss.elastic.co/t/startup-error-already-been-instantiated-using-full-framework-elastic-apm-agent/207707/2 "2019-11-13T13:40:32Z")

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Hi @NeoX

Since this issue is a potential bug (I'm not sure it's but it can be 🙂 and Github repo is the preferable place for bugs I propose to continue discussion regarding investigation and resolution in the Github issue. I left a comment there - please take a look.

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**Author:** ![system](https://us1.discourse-cdn.com/elastic/original/3X/1/a/1ac57faf039f6b580b3f104ef42a2a89e41014de.png) [@system](https://discuss.elastic.co/u/system)\
**Post date:** [December 4, 2019, 9:40am UTC](https://discuss.elastic.co/t/startup-error-already-been-instantiated-using-full-framework-elastic-apm-agent/207707/3 "2019-12-04T09:40:33Z")

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