Test failure: System.Net.Http.Functional.Tests.SocketsHttpHandler_DiagnosticsTest_Http2.SendAsync_ExpectedDiagnosticSourceActivityLoggingDoesNotOverwriteHeader

## Build Information
Build: https://dev.azure.com/dnceng-public/public/_build/results?buildId=1538638
Build error leg or test failing: System.Net.Http.Functional.Tests.SocketsHttpHandler_DiagnosticsTest_Http2.SendAsync_ExpectedDiagnosticSourceActivityLoggingDoesNotOverwriteHeader
```
System.Net.Http.Functional.Tests.SocketsHttpHandler_DiagnosticsTest_Http2.SendAsync_ExpectedDiagnosticSourceActivityLoggingDoesNotOverwriteHeader
[FAIL] System.Net.Http.Functional.Tests.SocketsHttpHandler_HttpClientHandler_ClientCertificates_Test.AutomaticOrManual_DoesntFailRegardlessOfWhetherClientCertsAreAvailable(mode: Automatic)
System.AggregateException : One or more errors occurred. (The SSL connection could not be established, see inner exception.) (Authentication failed, see inner exception.)
---- System.Net.Http.HttpRequestException : The SSL connection could not be established, see inner exception.
-------- System.Security.Authentication.AuthenticationException : Authentication failed, see inner exception.
------------ Interop+AppleCrypto+SslException : Internal error
---- System.Security.Authentication.AuthenticationException : Authentication failed, see inner exception.
-------- Interop+AppleCrypto+SslException : bad protocol version
at System.Threading.Tasks.TaskTimeoutExtensions.WhenAllOrAnyFailed(Task[] tasks) in /_/src/libraries/Common/tests/System/Threading/Tasks/TaskTimeoutExtensions.cs:line 87
at System.Net.Http.Functional.Tests.HttpClientHandler_ClientCertificates_Test.<>c__DisplayClass8_0.b__0(LoopbackServer server) in /_/src/libraries/Common/tests/System/Net/Http/HttpClientHandlerTest.ClientCertificates.cs:line 204
at System.Net.Test.Common.LoopbackServer.CreateServerAsync(Func`2 funcAsync, Options options) in /_/src/libraries/Common/tests/System/Net/Http/LoopbackServer.cs:line 107
at System.Net.Http.Functional.Tests.HttpClientHandler_ClientCertificates_Test.AutomaticOrManual_DoesntFailRegardlessOfWhetherClientCertsAreAvailable(ClientCertificateOption mode) in /_/src/libraries/Common/tests/System/Net/Http/HttpClientHandlerTest.ClientCertificates.cs:line 195
```

## Error Message

Fill the error message using [step by step known issues guidance](https://github.com/dotnet/arcade/blob/main/Documentation/Build%20Analysis/KnownIssueJsonStepByStep.md).

```json
{
"ErrorMessage": "Interop+AppleCrypto+SslException : Internal error",
"BuildRetry": false,
"ExcludeConsoleLog": false
}
```

### Known issue validation
**Build: :mag_right:** https://dev.azure.com/dnceng-public/public/_build/results?buildId=1538638
**Error message validated:** `[Interop+AppleCrypto+SslException : Internal error`]
**Result validation:** :white_check_mark: Known issue matched with the provided build.
**Validation performed at:** 8/4/2026 4:31:52 PM UTC

### Report

|Build|Repository|Test|Pull Request|
|---|---|---|---|
|[1593527](https://dev.azure.com/dnceng-public/public/_build/results?buildId=1593527)|dotnet/runtime|[System.Net.Http.Functional.Tests.SocketsHttpHandler_HttpClientHandler_ClientCertificates_Test.AutomaticOrManual_DoesntFailRegardlessOfWhetherClientCertsAreAvailable](https://dev.azure.com/dnceng-public/public/_build/results?buildId=1593527&view=ms.vss-test-web.build-test-results-tab&runId=43989678&resultId=178982)||
|[1593470](https://dev.azure.com/dnceng-public/public/_build/results?buildId=1593470)|dotnet/runtime|[System.Net.Http.Functional.Tests.SocketsHttpHandler_HttpClientHandler_ClientCertificates_Test.AutomaticOrManual_DoesntFailRegardlessOfWhetherClientCertsAreAvailable](https://dev.azure.com/dnceng-public/public/_build/results?buildId=1593470&view=ms.vss-test-web.build-test-results-tab&runId=43986080&resultId=204573)||
|[1592155](https://dev.azure.com/dnceng-public/public/_build/results?buildId=1592155)|dotnet/runtime|[System.Net.Http.Functional.Tests.SocketsHttpHandler_HttpClientHandler_ClientCertificates_Test.AutomaticOrManual_DoesntFailRegardlessOfWhetherClientCertsAreAvailable](https://dev.azure.com/dnceng-public/public/_build/results?buildId=1592155&view=ms.vss-test-web.build-test-results-tab&runId=43950578&resultId=218833)||
|[1588130](https://dev.azure.com/dnceng-public/public/_build/results?buildId=1588130)|dotnet/runtime|[System.Net.Http.Functional.Tests.SocketsHttpHandler_HttpClientHandler_ClientCertificates_Test.AutomaticOrManual_DoesntFailRegardlessOfWhetherClientCertsAreAvailable](https://dev.azure.com/dnceng-public/public/_build/results?buildId=1588130&view=ms.vss-test-web.build-test-results-tab&runId=43834258&resultId=217785)||
|[1585306](https://dev.azure.com/dnceng-public/public/_build/results?buildId=1585306)|dotnet/runtime|[System.Net.Http.Functional.Tests.SocketsHttpHandler_HttpClientHandler_ClientCertificates_Test.AutomaticOrManual_DoesntFailRegardlessOfWhetherClientCertsAreAvailable](https://dev.azure.com/dnceng-public/public/_build/results?buildId=1585306&view=ms.vss-test-web.build-test-results-tab&runId=43746280&resultId=202250)||
|[1585080](https://dev.azure.com/dnceng-public/public/_build/results?buildId=1585080)|dotnet/runtime|[System.Net.Http.Functional.Tests.SocketsHttpHandler_HttpClientHandler_ClientCertificates_Test.AutomaticOrManual_DoesntFailRegardlessOfWhetherClientCertsAreAvailable](https://dev.azure.com/dnceng-public/public/_build/results?buildId=1585080&view=ms.vss-test-web.build-test-results-tab&runId=43736482&resultId=188043)||
|[1583584](https://dev.azure.com/dnceng-public/public/_build/results?buildId=1583584)|dotnet/runtime|[System.Net.Http.Functional.Tests.SocketsHttpHandler_HttpClientHandler_ClientCertificates_Test.AutomaticOrManual_DoesntFailRegardlessOfWhetherClientCertsAreAvailable](https://dev.azure.com/dnceng-public/public/_build/results?buildId=1583584&view=ms.vss-test-web.build-test-results-tab&runId=43695598&resultId=224268)|dotnet/runtime#133257|
|[1583370](https://dev.azure.com/dnceng-public/public/_build/results?buildId=1583370)|dotnet/runtime|[System.Net.Http.Functional.Tests.SocketsHttpHandler_HttpClientHandler_ClientCertificates_Test.AutomaticOrManual_DoesntFailRegardlessOfWhetherClientCertsAreAvailable](https://dev.azure.com/dnceng-public/public/_build/results?buildId=1583370&view=ms.vss-test-web.build-test-results-tab&runId=43692672&resultId=225475)|dotnet/runtime#133250|
|[1582700](https://dev.azure.com/dnceng-public/public/_build/results?buildId=1582700)|dotnet/runtime|[System.Net.Http.Functional.Tests.SocketsHttpHandler_HttpClientHandler_ClientCertificates_Test.AutomaticOrManual_DoesntFailRegardlessOfWhetherClientCertsAreAvailable](https://dev.azure.com/dnceng-public/public/_build/results?buildId=1582700&view=ms.vss-test-web.build-test-results-tab&runId=43673696&resultId=176551)||
|[1581318](https://dev.azure.com/dnceng-public/public/_build/results?buildId=1581318)|dotnet/runtime|[System.Net.Http.Functional.Tests.SocketsHttpHandler_HttpClientHandler_ClientCertificates_Test.AutomaticOrManual_DoesntFailRegardlessOfWhetherClientCertsAreAvailable](https://dev.azure.com/dnceng-public/public/_build/results?buildId=1581318&view=ms.vss-test-web.build-test-results-tab&runId=43637794&resultId=224973)||
|[1581388](https://dev.azure.com/dnceng-public/public/_build/results?buildId=1581388)|dotnet/runtime|[System.Net.Http.Functional.Tests.SocketsHttpHandler_HttpClientHandler_ClientCertificates_Test.AutomaticOrManual_DoesntFailRegardlessOfWhetherClientCertsAreAvailable](https://dev.azure.com/dnceng-public/public/_build/results?buildId=1581388&view=ms.vss-test-web.build-test-results-tab&runId=43633722&resultId=185899)||
|[1578769](https://dev.azure.com/dnceng-public/public/_build/results?buildId=1578769)|dotnet/runtime|[System.Net.Http.Functional.Tests.SocketsHttpHandler_HttpClientHandler_ClientCertificates_Test.AutomaticOrManual_DoesntFailRegardlessOfWhetherClientCertsAreAvailable](https://dev.azure.com/dnceng-public/public/_build/results?buildId=1578769&view=ms.vss-test-web.build-test-results-tab&runId=43546078&resultId=225444)||
|[1578024](https://dev.azure.com/dnceng-public/public/_build/results?buildId=1578024)|dotnet/runtime|[System.Net.Http.Functional.Tests.SocketsHttpHandler_HttpClientHandler_ClientCertificates_Test.AutomaticOrManual_DoesntFailRegardlessOfWhetherClientCertsAreAvailable](https://dev.azure.com/dnceng-public/public/_build/results?buildId=1578024&view=ms.vss-test-web.build-test-results-tab&runId=43513786&resultId=233290)||
|[1577670](https://dev.azure.com/dnceng-public/public/_build/results?buildId=1577670)|dotnet/runtime|[System.Net.Http.Functional.Tests.SocketsHttpHandler_HttpClientHandler_ClientCertificates_Test.AutomaticOrManual_DoesntFailRegardlessOfWhetherClientCertsAreAvailable](https://dev.azure.com/dnceng-public/public/_build/results?buildId=1577670&view=ms.vss-test-web.build-test-results-tab&runId=43511400&resultId=174142)||
|[1577668](https://dev.azure.com/dnceng-public/public/_build/results?buildId=1577668)|dotnet/runtime|[System.Net.Http.Functional.Tests.SocketsHttpHandler_HttpClientHandler_ClientCertificates_Test.AutomaticOrManual_DoesntFailRegardlessOfWhetherClientCertsAreAvailable](https://dev.azure.com/dnceng-public/public/_build/results?buildId=1577668&view=ms.vss-test-web.build-test-results-tab&runId=43503096&resultId=232390)||
|[1577496](https://dev.azure.com/dnceng-public/public/_build/results?buildId=1577496)|dotnet/runtime|[System.Net.Http.Functional.Tests.SocketsHttpHandler_HttpClientHandler_ClientCertificates_Test.AutomaticOrManual_DoesntFailRegardlessOfWhetherClientCertsAreAvailable](https://dev.azure.com/dnceng-public/public/_build/results?buildId=1577496&view=ms.vss-test-web.build-test-results-tab&runId=43502910&resultId=176459)|dotnet/runtime#132932|
|[1576293](https://dev.azure.com/dnceng-public/public/_build/results?buildId=1576293)|dotnet/runtime|[System.Net.Http.Functional.Tests.SocketsHttpHandler_HttpClientHandler_ClientCertificates_Test.AutomaticOrManual_DoesntFailRegardlessOfWhetherClientCertsAreAvailable](https://dev.azure.com/dnceng-public/public/_build/results?buildId=1576293&view=ms.vss-test-web.build-test-results-tab&runId=43461058&resultId=174764)||
|[1575919](https://dev.azure.com/dnceng-public/public/_build/results?buildId=1575919)|dotnet/runtime|[System.Net.Http.Functional.Tests.SocketsHttpHandler_HttpClientHandler_ClientCertificates_Test.AutomaticOrManual_DoesntFailRegardlessOfWhetherClientCertsAreAvailable](https://dev.azure.com/dnceng-public/public/_build/results?buildId=1575919&view=ms.vss-test-web.build-test-results-tab&runId=43440694&resultId=218292)|dotnet/runtime#132872|
|[1575442](https://dev.azure.com/dnceng-public/public/_build/results?buildId=1575442)|dotnet/runtime|[System.Net.Http.Functional.Tests.SocketsHttpHandler_HttpClientHandler_ClientCertificates_Test.AutomaticOrManual_DoesntFailRegardlessOfWhetherClientCertsAreAvailable](https://dev.azure.com/dnceng-public/public/_build/results?buildId=1575442&view=ms.vss-test-web.build-test-results-tab&runId=43431574&resultId=178621)||
|[1574568](https://dev.azure.com/dnceng-public/public/_build/results?buildId=1574568)|dotnet/runtime|[System.Net.Http.Functional.Tests.SocketsHttpHandler_HttpClientHandler_ClientCertificates_Test.AutomaticOrManual_DoesntFailRegardlessOfWhetherClientCertsAreAvailable](https://dev.azure.com/dnceng-public/public/_build/results?buildId=1574568&view=ms.vss-test-web.build-test-results-tab&runId=43397292&resultId=202010)||
|[1573573](https://dev.azure.com/dnceng-public/public/_build/results?buildId=1573573)|dotnet/runtime|[System.Net.Http.Functional.Tests.SocketsHttpHandler_HttpClientHandler_ClientCertificates_Test.AutomaticOrManual_DoesntFailRegardlessOfWhetherClientCertsAreAvailable](https://dev.azure.com/dnceng-public/public/_build/results?buildId=1573573&view=ms.vss-test-web.build-test-results-tab&runId=43353046&resultId=197823)||
|[1570973](https://dev.azure.com/dnceng-public/public/_build/results?buildId=1570973)|dotnet/runtime|[System.Net.Http.Functional.Tests.SocketsHttpHandler_HttpClientHandler_ClientCertificates_Test.AutomaticOrManual_DoesntFailRegardlessOfWhetherClientCertsAreAvailable](https://dev.azure.com/dnceng-public/public/_build/results?buildId=1570973&view=ms.vss-test-web.build-test-results-tab&runId=43265308&resultId=223989)||
|[1570314](https://dev.azure.com/dnceng-public/public/_build/results?buildId=1570314)|dotnet/runtime|[System.Net.Http.Functional.Tests.SocketsHttpHandler_HttpClientHandler_ClientCertificates_Test.AutomaticOrManual_DoesntFailRegardlessOfWhetherClientCertsAreAvailable](https://dev.azure.com/dnceng-public/public/_build/results?buildId=1570314&view=ms.vss-test-web.build-test-results-tab&runId=43246164&resultId=224002)||
|[1563754](https://dev.azure.com/dnceng-public/public/_build/results?buildId=1563754)|dotnet/runtime|[System.Net.Http.Functional.Tests.SocketsHttpHandler_HttpClientHandler_ClientCertificates_Test.AutomaticOrManual_DoesntFailRegardlessOfWhetherClientCertsAreAvailable](https://dev.azure.com/dnceng-public/public/_build/results?buildId=1563754&view=ms.vss-test-web.build-test-results-tab&runId=43056510&resultId=132839)||
|[1563512](https://dev.azure.com/dnceng-public/public/_build/results?buildId=1563512)|dotnet/runtime|[System.Net.Http.Functional.Tests.SocketsHttpHandler_HttpClientHandler_ClientCertificates_Test.AutomaticOrManual_DoesntFailRegardlessOfWhetherClientCertsAreAvailable](https://dev.azure.com/dnceng-public/public/_build/results?buildId=1563512&view=ms.vss-test-web.build-test-results-tab&runId=43045564&resultId=218687)||
|[1563356](https://dev.azure.com/dnceng-public/public/_build/results?buildId=1563356)|dotnet/runtime|[System.Net.Http.Functional.Tests.SocketsHttpHandler_HttpClientHandler_ClientCertificates_Test.AutomaticOrManual_DoesntFailRegardlessOfWhetherClientCertsAreAvailable](https://dev.azure.com/dnceng-public/public/_build/results?buildId=1563356&view=ms.vss-test-web.build-test-results-tab&runId=43039092&resultId=218112)|dotnet/runtime#132649|
|[1562367](https://dev.azure.com/dnceng-public/public/_build/results?buildId=1562367)|dotnet/runtime|[System.Net.Http.Functional.Tests.SocketsHttpHandler_HttpClientHandler_ClientCertificates_Test.AutomaticOrManual_DoesntFailRegardlessOfWhetherClientCertsAreAvailable](https://dev.azure.com/dnceng-public/public/_build/results?buildId=1562367&view=ms.vss-test-web.build-test-results-tab&runId=43017476&resultId=137901)||
#### Summary
|24-Hour Hit Count|7-Day Hit Count|1-Month Count|
|---|---|---|
|0|4|27|

Start with the failing client-certificate test in Common/tests/System/Net/Http/HttpClientHandlerTest.ClientCertificates.cs and the LoopbackServer call at the reported lines. Read the known-issue guidance, then compare the AppleCrypto SSL failure with the ErrorMessage and validation report; done means the failure classification and build handling are verified against the affected test.

Written by the indexing model from the issue text.