# Cannot resolve dependency to assembly FSharp.Core

**URL:** <https://forums.fsharp.org/t/cannot-resolve-dependency-to-assembly-fsharp-core/313>\
**Category:** General\
**Created:** [July 5, 2018, 10:28am UTC](https://forums.fsharp.org/t/cannot-resolve-dependency-to-assembly-fsharp-core/313 "2018-07-05T10:28:15Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![Bridges](https://avatars.discourse-cdn.com/v4/letter/b/5f8ce5/32.png) [@Bridges](https://forums.fsharp.org/u/Bridges)\
**Post date:** [July 5, 2018, 10:28am UTC](https://forums.fsharp.org/t/cannot-resolve-dependency-to-assembly-fsharp-core/313/1 "2018-07-05T10:28:15Z")

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In a WPF programm with a Fsharp Library, I get the error message:

Unknown build error, ‘Cannot resolve dependency to assembly ‘FSharp.Core, Version=4.4.3.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a’ because it has not been preloaded. When using the ReflectionOnly APIs, dependent assemblies must be pre-loaded or loaded on demand through the ReflectionOnlyAssemblyResolve event.’

Any suggesions on how to solve this?

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**Author:** ![giuliohome](https://yyz2.discourse-cdn.com/flex030/user_avatar/forums.fsharp.org/giuliohome/32/202_2.png) [@giuliohome](https://forums.fsharp.org/u/giuliohome)\
**Post date:** [July 5, 2018, 10:31am UTC](https://forums.fsharp.org/t/cannot-resolve-dependency-to-assembly-fsharp-core/313/2 "2018-07-05T10:31:23Z")

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Using nuget to get the correct FSharp.Core.

Also notice that the framework version is relevant: e.g. 4.6 vs 4.5

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<div class="post-metadata">

**Author:** ![Bridges](https://avatars.discourse-cdn.com/v4/letter/b/5f8ce5/32.png) [@Bridges](https://forums.fsharp.org/u/Bridges)\
**Post date:** [July 5, 2018, 11:42am UTC](https://forums.fsharp.org/t/cannot-resolve-dependency-to-assembly-fsharp-core/313/3 "2018-07-05T11:42:22Z")

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Thanks for your swift reply.

I updated Fsharp.Core to the latest version 4.5.

I get the same error message, although referring to Version=4.5.0.0.

In what way is the framework version relevant? In the WPF project the framework is set to 4.6.1. In the f# project I can only set the framework to .net standard…

![image](https://canada1.discourse-cdn.com/flex030/uploads/fsharp/original/1X/1573e2c2fa5ec1d8a87c61ca0f99678c15c2f99c.png)

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<div class="post-metadata">

**Author:** ![giuliohome](https://yyz2.discourse-cdn.com/flex030/user_avatar/forums.fsharp.org/giuliohome/32/202_2.png) [@giuliohome](https://forums.fsharp.org/u/giuliohome)\
**Post date:** [July 5, 2018, 12:01pm UTC](https://forums.fsharp.org/t/cannot-resolve-dependency-to-assembly-fsharp-core/313/4 "2018-07-05T12:01:35Z")

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My first question would be:  
In the WPF project, did you install the corresponding Fsharp.Core via nuget?

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<div class="post-metadata">

**Author:** ![Bridges](https://avatars.discourse-cdn.com/v4/letter/b/5f8ce5/32.png) [@Bridges](https://forums.fsharp.org/u/Bridges)\
**Post date:** [July 5, 2018, 12:34pm UTC](https://forums.fsharp.org/t/cannot-resolve-dependency-to-assembly-fsharp-core/313/5 "2018-07-05T12:34:12Z")

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that worked, thanks!