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README.md

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 ## Announcement
 
+* Profiler 2.1.0-beta2 is **NOT** recommended. There is a bug that impacts the ASP.NET Core application starting up. See bug #85 for details. Please wait for 2.1.0-beta3.
+
+## Previous announcements
+
 * Profiler 2.1.0-beta1 is [available now](https://www.nuget.org/packages/Microsoft.ApplicationInsights.Profiler.AspNetCore/2.1.0-beta1). Read [What's new](./docs/WhatIsNew2_0.md) and [Migrate to Application Insights Profiler 2.0](./docs/MigrateTo2_0.md). Follow the example of [quick start](./examples/QuickStart3_0/Readme.md) if you are building a new app service.
 
   * [Break change] Application Insights Profiler 2.1.0-* depends on [Application Insights SDK for ASP.NET Core 2.12.0](https://www.nuget.org/packages/Microsoft.ApplicationInsights.AspNetCore/2.12.0) and above. It will be referenced implicitly.