Unable to load DLL 'Microsoft.Data.SqlClient.SNI.x86.dll' in an environment and all ok in another

[davide882]

Good morning,
I have a .net framework 4.8 application that reference in the api project Microsoft.Data.SqlClient and Microsoft.Data.SqlClient.SNI.
All it's fine in my local machine and in our testing server, but when I deploy the application in the customer staging environment I get the error
Unable to load DLL 'Microsoft.Data.SqlClient.SNI.x86.dll': The specified module could not be found. (Exception from HRESULT: 0x8007007E)

dll are there, so I can't understood why the application doesn't work in that environment: any ideas?

The complete stack trace of the exception is the following:

[DllNotFoundException: Unable to load DLL 'Microsoft.Data.SqlClient.SNI.x86.dll': The specified module could not be found. (Exception from HRESULT: 0x8007007E)]
   Microsoft.Data.SqlClient.SNINativeManagedWrapperX86.SNIInitialize(IntPtr pmo) +0
   Microsoft.Data.SqlClient.SNINativeMethodWrapper.SNIInitialize(IntPtr pmo) in D:\a\_work\1\s\src\Microsoft.Data.SqlClient\netfx\src\Microsoft\Data\Interop\SNINativeMethodWrapper.cs:799
   Microsoft.Data.SqlClient.SNILoadHandle..ctor() in D:\a\_work\1\s\src\Microsoft.Data.SqlClient\src\Microsoft\Data\SqlClient\TdsParserSafeHandles.Windows.cs:28
   Microsoft.Data.SqlClient.SNILoadHandle..cctor() in D:\a\_work\1\s\src\Microsoft.Data.SqlClient\src\Microsoft\Data\SqlClient\TdsParserSafeHandles.Windows.cs:19

[TypeInitializationException: The type initializer for 'Microsoft.Data.SqlClient.SNILoadHandle' threw an exception.]
   Microsoft.Data.SqlClient.TdsParser..cctor() in D:\a\_work\1\s\src\Microsoft.Data.SqlClient\netfx\src\Microsoft\Data\SqlClient\TdsParser.cs:181

[TypeInitializationException: The type initializer for 'Microsoft.Data.SqlClient.TdsParser' threw an exception.]
   Microsoft.Data.SqlClient.TdsParser..ctor(Boolean MARS, Boolean fAsynchronous) in D:\a\_work\1\s\src\Microsoft.Data.SqlClient\netfx\src\Microsoft\Data\SqlClient\TdsParser.cs:38
   Microsoft.Data.SqlClient.SqlInternalConnectionTds.LoginNoFailover(ServerInfo serverInfo, String newPassword, SecureString newSecurePassword, Boolean redirectedUserInstance, SqlConnectionString connectionOptions, SqlCredential credential, TimeoutTimer timeout) in D:\a\_work\1\s\src\Microsoft.Data.SqlClient\netfx\src\Microsoft\Data\SqlClient\SqlInternalConnectionTds.cs:1838
   Microsoft.Data.SqlClient.SqlInternalConnectionTds.OpenLoginEnlist(TimeoutTimer timeout, SqlConnectionString connectionOptions, SqlCredential credential, String newPassword, SecureString newSecurePassword, Boolean redirectedUserInstance) in D:\a\_work\1\s\src\Microsoft.Data.SqlClient\netfx\src\Microsoft\Data\SqlClient\SqlInternalConnectionTds.cs:1727
   Microsoft.Data.SqlClient.SqlInternalConnectionTds..ctor(DbConnectionPoolIdentity identity, SqlConnectionString connectionOptions, SqlCredential credential, Object providerInfo, String newPassword, SecureString newSecurePassword, Boolean redirectedUserInstance, SqlConnectionString userConnectionOptions, SessionData reconnectSessionData, ServerCertificateValidationCallback serverCallback, ClientCertificateRetrievalCallback clientCallback, DbConnectionPool pool, String accessToken, SqlClientOriginalNetworkAddressInfo originalNetworkAddressInfo, Boolean applyTransientFaultHandling) in D:\a\_work\1\s\src\Microsoft.Data.SqlClient\netfx\src\Microsoft\Data\SqlClient\SqlInternalConnectionTds.cs:539
   Microsoft.Data.SqlClient.SqlConnectionFactory.CreateConnection(DbConnectionOptions options, DbConnectionPoolKey poolKey, Object poolGroupProviderInfo, DbConnectionPool pool, DbConnection owningConnection, DbConnectionOptions userOptions) in D:\a\_work\1\s\src\Microsoft.Data.SqlClient\netfx\src\Microsoft\Data\SqlClient\SqlConnectionFactory.cs:143
   Microsoft.Data.ProviderBase.DbConnectionFactory.CreatePooledConnection(DbConnectionPool pool, DbConnection owningObject, DbConnectionOptions options, DbConnectionPoolKey poolKey, DbConnectionOptions userOptions) in D:\a\_work\1\s\src\Microsoft.Data.SqlClient\netfx\src\Microsoft\Data\ProviderBase\DbConnectionFactory.cs:148
   Microsoft.Data.ProviderBase.DbConnectionPool.CreateObject(DbConnection owningObject, DbConnectionOptions userOptions, DbConnectionInternal oldConnection) in D:\a\_work\1\s\src\Microsoft.Data.SqlClient\netfx\src\Microsoft\Data\ProviderBase\DbConnectionPool.cs:950
   Microsoft.Data.ProviderBase.DbConnectionPool.UserCreateRequest(DbConnection owningObject, DbConnectionOptions userOptions, DbConnectionInternal oldConnection) in D:\a\_work\1\s\src\Microsoft.Data.SqlClient\netfx\src\Microsoft\Data\ProviderBase\DbConnectionPool.cs:2014
   Microsoft.Data.ProviderBase.DbConnectionPool.TryGetConnection(DbConnection owningObject, UInt32 waitForMultipleObjectsTimeout, Boolean allowCreate, Boolean onlyOneCheckConnection, DbConnectionOptions userOptions, DbConnectionInternal& connection) in D:\a\_work\1\s\src\Microsoft.Data.SqlClient\netfx\src\Microsoft\Data\ProviderBase\DbConnectionPool.cs:1419
   Microsoft.Data.ProviderBase.DbConnectionPool.TryGetConnection(DbConnection owningObject, TaskCompletionSource`1 retry, DbConnectionOptions userOptions, DbConnectionInternal& connection) in D:\a\_work\1\s\src\Microsoft.Data.SqlClient\netfx\src\Microsoft\Data\ProviderBase\DbConnectionPool.cs:1303
   Microsoft.Data.ProviderBase.DbConnectionFactory.TryGetConnection(DbConnection owningConnection, TaskCompletionSource`1 retry, DbConnectionOptions userOptions, DbConnectionInternal oldConnection, DbConnectionInternal& connection) in D:\a\_work\1\s\src\Microsoft.Data.SqlClient\netfx\src\Microsoft\Data\ProviderBase\DbConnectionFactory.cs:339
   Microsoft.Data.ProviderBase.DbConnectionInternal.TryOpenConnectionInternal(DbConnection outerConnection, DbConnectionFactory connectionFactory, TaskCompletionSource`1 retry, DbConnectionOptions userOptions) in D:\a\_work\1\s\src\Microsoft.Data.SqlClient\netfx\src\Microsoft\Data\ProviderBase\DbConnectionInternal.cs:770
   Microsoft.Data.ProviderBase.DbConnectionClosed.TryOpenConnection(DbConnection outerConnection, DbConnectionFactory connectionFactory, TaskCompletionSource`1 retry, DbConnectionOptions userOptions) in D:\a\_work\1\s\src\Microsoft.Data.SqlClient\netfx\src\Microsoft\Data\ProviderBase\DbConnectionClosed.cs:71
   Microsoft.Data.SqlClient.SqlConnection.TryOpenInner(TaskCompletionSource`1 retry) in D:\a\_work\1\s\src\Microsoft.Data.SqlClient\netfx\src\Microsoft\Data\SqlClient\SqlConnection.cs:2113
   Microsoft.Data.SqlClient.SqlConnection.TryOpen(TaskCompletionSource`1 retry, SqlConnectionOverrides overrides) in D:\a\_work\1\s\src\Microsoft.Data.SqlClient\netfx\src\Microsoft\Data\SqlClient\SqlConnection.cs:2101
   Microsoft.Data.SqlClient.SqlConnection.Open(SqlConnectionOverrides overrides) in D:\a\_work\1\s\src\Microsoft.Data.SqlClient\netfx\src\Microsoft\Data\SqlClient\SqlConnection.cs:1658
   Microsoft.Data.SqlClient.SqlConnection.Open() in D:\a\_work\1\s\src\Microsoft.Data.SqlClient\netfx\src\Microsoft\Data\SqlClient\SqlConnection.cs:1627
   Hangfire.SqlServer.SqlServerStorage.CreateAndOpenConnection() +208
   Hangfire.SqlServer.SqlServerStorage.UseConnection(DbConnection dedicatedConnection, Func`2 func) +50
   Hangfire.SqlServer.SqlServerStorage.UseConnection(DbConnection dedicatedConnection, Action`1 action) +71
   Hangfire.SqlServer.SqlServerStorage.Initialize() +185
   Hangfire.SqlServer.SqlServerStorage..ctor(String nameOrConnectionString, SqlServerStorageOptions options) +403
   Hangfire.SqlServerStorageExtensions.UseSqlServerStorage(IGlobalConfiguration configuration, String nameOrConnectionString, SqlServerStorageOptions options) +52
   Sgr.MyApp.WebAPI.Scheduler.HangfireBootstrapper.Start() in C:\Software\GBS\MyApp\Sgr.MyApp.WebAPI\Scheduler\HangfireBootstrapper.cs:36
   Sgr.MyApp.WebAPI.WebApiApplication.Application_Start() in C:\Software\GBS\MyApp\Sgr.MyApp.WebAPI\Global.asax.cs:125

[HttpException (0x80004005): The type initializer for 'Microsoft.Data.SqlClient.TdsParser' threw an exception.]
   System.Web.HttpApplicationFactory.EnsureAppStartCalledForIntegratedMode(HttpContext context, HttpApplication app) +476
   System.Web.HttpApplication.RegisterEventSubscriptionsWithIIS(IntPtr appContext, HttpContext context, MethodInfo[] handlers) +118
   System.Web.HttpApplication.InitSpecial(HttpApplicationState state, MethodInfo[] handlers, IntPtr appContext, HttpContext context) +176
   System.Web.HttpApplicationFactory.GetSpecialApplicationInstance(IntPtr appContext, HttpContext context) +220
   System.Web.Hosting.PipelineRuntime.InitializeApplication(IntPtr appContext) +303

[HttpException (0x80004005): The type initializer for 'Microsoft.Data.SqlClient.TdsParser' threw an exception.]
   System.Web.HttpRuntime.FirstRequestInit(HttpContext context) +659
   System.Web.HttpRuntime.EnsureFirstRequestInit(HttpContext context) +89
   System.Web.HttpRuntime.ProcessRequestNotificationPrivate(IIS7WorkerRequest wr, HttpContext context) +189

[Kaur-Parminder]

@davide882 What is the type of the project? if this is a Web App, it is potential duplicate of existing issues. Please provide a Repro or steps to reproduce the issue.

[davide882]

Hi, it's a web app in .net framework 4.8.
I don't know ho to reproduce the error: on my machine and on my company test server it works, on customer staging environment it doesn't work.

MyWebAPI.zip

[JRahnama]

@davide882 so, from what I could understand inside the project in the path of bin/Release or debug/net48 you are able to see the required dll, but application is not able to find it?

[David-Engel]

You might be missing the VC runtime in that environment, required by the SNI DLL:
https://learn.microsoft.com/en-us/cpp/windows/latest-supported-vc-redist?view=msvc-170#visual-studio-2015-2017-2019-and-2022

[davide882]

@davide882 so, from what I could understand inside the project in the path of bin/Release or debug/net48 you are able to see the required dll, but application is not able to find it?

Exactlty

[davide882]

These are the vc installed on the customer enviroment

[davide882]

The application is developed with Visual Studio 2022 and in my enviroment, where all works correctly, I have the following VC installed.

It could be the missing Microsoft Visual C++ 2015-2022 Redistributable (x86 and x64) on the Customer environment the problem?

[David-Engel]

Closing as duplicate of #446