Network Management

SolarWinds Information Service fails to start in SolarWinds Platform 2025.4 due to conflicting System.Threading.Tasks.Extensions version

This article describes an issue where the SolarWinds Information Service and the SolarWinds Collector Service fail to start when a conflicting version of the System.Threading.Tasks.Extensions assembly is present in the Global Assembly Cache (GAC) on the server.

First published date

1/23/2026 10:11 PM

Last published date

7/29/2026 10:38 PM

Overview

This issue can cause the Configuration Wizard to fail during the step Verifying that the SWIS service is available.

Symptoms

Note: 

This article applies only if the errors described in the SolarWinds Information Service or Collector Service logs are present.

The Configuration Wizard error alone is not sufficient to indicate this issue, as it may appear in other scenarios where the service fails to start for different reasons.

Configuration Wizard Error:

When running the Configuration Wizard, you may see:

Verifying that the SWIS service is available FAILED

 

Services configuration failed: • Connection to SolarWinds® Information Service did not succeed. Last error: There was no endpoint listening at net.tcp://<hostname>:17777/SolarWinds/InformationService/v3/Orion/certificate that could accept the message. This is often caused by an incorrect address or SOAP action.

SWIS Log Error:

In the SolarWinds Information Service log (C:\Program Data\SolarWinds\InformationService\v3.0\) you may find error:

2025-11-24 16:44:41,364 [7] ERROR SolarWinds.InformationService.Core.InformationServiceService -

(null) (null)         Information Service failed to open a channel.

System.Reflection.TargetInvocationException: Exception has been thrown by the target of an invocation. ---> System.MissingMethodException: Method not found: 'Void Polly.Retry.RetryStrategyOptions`1.set_ShouldHandle(System.Func`2<Polly.Retry.RetryPredicateArguments`1<!0>,System.Threading.Tasks.ValueTask`1<Boolean>>)'.

 

Collector Service Log Error:

In the Collector ServiceHost log (C:\ProgramData\SolarWinds\Collector\Logs\) you may find the following error:

2025-11-24 16:43:00,897 [7] FATAL SolarWinds.Collector.CollectorService -

(null)  Unhandled exception caught.

System.MissingMethodException: Method not found: 'Void Polly.Retry.RetryStrategyOptions`1.set_ShouldHandle(System.Func`2<Polly.Retry.RetryPredicateArguments`1<!0>,System.Threading.Tasks.ValueTask`1<Boolean>>)'.

Product section

Orion Platform

Cause

If there is a version of the System.Threading.Tasks.Extensions assembly present in the GAC that does not match the version shipped with the SolarWinds Platform, each service may load multiple versions of that assembly into the process simultaneously.

This can lead to type-identity mismatches, resulting in a MissingMethodException and preventing the services from starting.

Resolution

This issue is addressed in SolarWinds Platform 2026.2. Consider upgrading your environment. If you cannot upgrade, use the workaround below:

Add a binding redirect section to the configuration files below:

  • SolarWinds.InformationService.Service.exe.config

  • SolarWinds.Collector.ServiceHost.config

These files are located in the SolarWinds installation directory, by default at C:\Program Files\SolarWinds\Orion.

 

Insert the following inside the <runtime> section:

<assemblyBinding xmlns="urn:schemas-microsoft-com:asm.v1">

      <dependentAssembly>

        <assemblyIdentity name="System.Threading.Tasks.Extensions" publicKeyToken="cc7b13ffcd2ddd51" culture="neutral" />

        <bindingRedirect oldVersion="0.0.0.0-4.2.1.0" newVersion="4.2.1.0" />

      </dependentAssembly>

 </assemblyBinding>

Save the files and rerun the Configuration Wizard.