The communication to the main polling engine server failed. "Object reference is not set to an instance of an object" when installing on APE

10/29/2024 12:27 AM

11/14/2025 5:53 PM

Customers will encounter the error, An error has occurred. Object reference is not set to an instance of an object when installing SolarWinds on the Additional Polling Engine on version 2024.4 and below.

 

Upon checking the Administration service.Client.log, you will see the error below.

2024-10-18 12:01:21,107 [28] ERROR (null) SolarWinds.Administration.DataProviders.CachingProductCatalogProvider - Cannot read the cached Product Catalog. System.InvalidOperationException: Cannot read Product Catalog from the cache

2024-10-18 12:01:21,089 [28] INFO (null) SolarWinds.Administration.DataProviders.CachingProductCatalogProvider - Cached product catalog version is equal or higher than remote product catalog version - using cached product catalog.
2024-10-18 12:01:21,097 [28] ERROR (null) SolarWinds.Administration.Parser.JsonSerializerWrapper - Error reading JObject from JsonReader. Current JsonReader item is not an object: Null. Path 'Catalog[0].Installers[1].Conditions[0]', line 1, position 1115.
Newtonsoft.Json.JsonReaderException: Error reading JObject from JsonReader. Current JsonReader item is not an object: Null. Path 'Catalog[0].Installers[1].Conditions[0]', line 1, position 1115.
at Newtonsoft.Json.Linq.JObject.Load(JsonReader reader, JsonLoadSettings settings)
at SolarWinds.ReleaseManagement.Model.JsonConverters.ConditionTypeConverter.ReadJson(JsonReader reader, Type objectType, Object existingValue, JsonSerializer serializer)

2024-10-18 12:01:21,106 [28] DEBUG (null) SolarWinds.Administration.DataProviders.PersistenceProvider - Cannot deserialize file C:\ProgramData\SolarWinds\Installers\SolarWinds.Administration.ProductCatalog.Model.ProductCatalogModel_observability.json.
2024-10-18 12:01:21,107 [28] ERROR (null) SolarWinds.Administration.DataProviders.CachingProductCatalogProvider - Cannot read cached Product Catalog. System.InvalidOperationException: Cannot read Product Catalog from cache
at SolarWinds.Administration.DataProviders.PersistedProductCatalogProvider.GetProductCatalogModel()
at SolarWinds.Administration.DataProviders.CachingProductCatalogProvider.LoadCachedProductCatalogOrNull()

2024-10-18 12:01:21,111 [28] ERROR (null) SolarWinds.Administration.Installer.ErrorHandler.HttpResponseAdapter - Unexpected error occured.
System.NullReferenceException: Object reference not set to an instance of an object.
at SolarWinds.Administration.DataProviders.CachingProductCatalogProvider.DownloadProductCatalogFromSource()

 

Hybrid Cloud Observability

This is a known bug that happens on version 2024.4 and below.

 

 

This issue is addressed in SolarWinds Platform 2025.1. Consider upgrading your environment. If you can't upgrade, use the workaround below.

Workaround:

Try to install APE using the installer from the Main Polling Engine.

1. Remove product catalog json from the Installers folder on the Main Polling Engine.

2. Restart the SolarWinds Administration service on the Main Polling Engine.

3. Go to /apps/settings/polling-engines-details and click Download Installer in the upper right corner.

4. Remove C:\ProgramData\Solarwinds folder on the Additional Polling Engine.

5. Use the downloaded installer ("SolarWinds-Installer.exe") and run the installer in the Additional Polling Engine.