Execute 'RunSyncJob' Error : The remote server returned an error: (404) Not Found.

Topic

The following errors are repeatedly logged in the HostServer logs:

"Error","General","0","ErrorMessage","SourceCode.Sync.Runtime.SyncService","0 Execute 'RunSyncJob' Error : The remote server returned an error: (404) Not Found."

"Error","General","0","ErrorMessage","SourceCode.Sync.Runtime.SyncProviderLogger","0 EnvironmentId: {environmentID}, Error - The remote server returned an error: (404) Not Found."

The error messages suggest this was thrown when K2 was trying to perform a sync operation. Checking the [SyncEngine].[RunHistory] and listing the most recent records show the same 404 error was repeatedly thrown on sync operations for specific ProviderInstanceID.

Instructions 

The 404 error was thrown by the identity provider that K2 was trying to sync the users and groups from. The first step is to figure out which Provider and ProviderInstance the sync was for.

Once you have identified the ProviderInstanceID of the sync operation that was throwing the 404 error from [SyncEngine],[RunHistory], you can run the following on the K2 database to retrieve information about the ProviderInstance and its Provider:

SELECT P.[Name] AS ProviderName, T.[Type] AS ProviderType, PI.[ID] AS ProviderInstanceID, PI.[SyncState], PI.[Name], PI.[ActiveServerID], PI.[SyncIntervalMinutes], PI.[LastSyncDateOffset]
FROM [SyncEngine].[ProviderInstance] AS PI
INNER JOIN [SyncEngine].[Provider] AS P
ON PI.[ProviderID] = P.[ID]
INNER JOIN [SyncEngine].[ProviderType] AS T
ON P.[ProviderTypeID] = T.[ID]
WHERE PI.[ID] = <insert ProviderInstanceID here>

A 404 error simply means a page or service is not found, so this suggests the identity provider is not accessible from the K2 server. If you still require the users and groups to be synced from that ProviderInstance, you need to make sure the identity provider that K2 is trying to sync from is accessible from the K2 server.

For example, if the 404 error was thrown when K2 was trying to sync identities from a specific SharePoint site, you need to make sure the SharePoint site is accessible from the K2 server.