Windows 10
Version 20H2 (OS Build 19042.1415)
New installation: My Movies for Windows - Windows 7, 8 or 10 Version 5.40
Same error for the standalone and/or server/client option.
I did a complete uninstall/reinstall of mymovies + sql server

From the log:
...
2022-01-11 17:20:32 . 25 - A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: SQL Network Interfaces, error: 25 - Connection string is not valid) at System.Data.SqlClient.SqlInternalConnectionTds..ctor(DbConnectionPoolIdentity identity, SqlConnectionString connectionOptions, SqlCredential credential, Object providerInfo, String newPassword, SecureString newSecurePassword, Boolean redirectedUserInstance, SqlConnectionString userConnectionOptions, SessionData reconnectSessionData, DbConnectionPool pool, String accessToken, Boolean applyTransientFaultHandling, SqlAuthenticationProviderManager sqlAuthProviderManager)
at System.Data.SqlClient.SqlConnectionFactory.CreateConnection(DbConnectionOptions options, DbConnectionPoolKey poolKey, Object poolGroupProviderInfo, DbConnectionPool pool, DbConnection owningConnection, DbConnectionOptions userOptions)
at System.Data.ProviderBase.DbConnectionFactory.CreatePooledConnection(DbConnectionPool pool, DbConnection owningObject, DbConnectionOptions options, DbConnectionPoolKey poolKey, DbConnectionOptions userOptions)
at System.Data.ProviderBase.DbConnectionPool.CreateObject(DbConnection owningObject, DbConnectionOptions userOptions, DbConnectionInternal oldConnection)
at System.Data.ProviderBase.DbConnectionPool.UserCreateRequest(DbConnection owningObject, DbConnectionOptions userOptions, DbConnectionInternal oldConnection)
at System.Data.ProviderBase.DbConnectionPool.TryGetConnection(DbConnection owningObject, UInt32 waitForMultipleObjectsTimeout, Boolean allowCreate, Boolean onlyOneCheckConnection, DbConnectionOptions userOptions, DbConnectionInternal& connection)
at System.Data.ProviderBase.DbConnectionPool.TryGetConnection(DbConnection owningObject, TaskCompletionSource`1 retry, DbConnectionOptions userOptions, DbConnectionInternal& connection)
at System.Data.ProviderBase.DbConnectionFactory.TryGetConnection(DbConnection owningConnection, TaskCompletionSource`1 retry, DbConnectionOptions userOptions, DbConnectionInternal oldConnection, DbConnectionInternal& connection)
at System.Data.ProviderBase.DbConnectionInternal.TryOpenConnectionInternal(DbConnection outerConnection, DbConnectionFactory connectionFactory, TaskCompletionSource`1 retry, DbConnectionOptions userOptions)
at System.Data.SqlClient.SqlConnection.TryOpenInner(TaskCompletionSource`1 retry)
at System.Data.SqlClient.SqlConnection.TryOpen(TaskCompletionSource`1 retry)
at System.Data.SqlClient.SqlConnection.Open()
at MyMovies.Database.OpenConn(SqlConnection objConn, Boolean bolLog) in Y:\Documents\Visual Studio 2019\Projects\My Movies for WMC and CM 5.10\My Movies Common\Database\Database.vbine 1391
at MyMovies.CollectionManagement.LoadTitleList(Int32 intSelectId, String strSelectId, Int32 intSelectParentId, String strSelectParentId) in Y:\Documents\Visual Studio 2019\Projects\My Movies for WMC and CM 5.10\My Movies - Collection\Collection Management.vbine 5789
at MyMovies.CollectionManagement.nbcNavigationBar_GroupExpanded() in Y:\Documents\Visual Studio 2019\Projects\My Movies for WMC and CM 5.10\My Movies - Collection\Collection Management.vbine 22109
at MyMovies.CollectionManagement.BuildInterface() in Y:\Documents\Visual Studio 2019\Projects\My Movies for WMC and CM 5.10\My Movies - Collection\Collection Management.vbine 2589
at MyMovies.CollectionManagement..ctor() in Y:\Documents\Visual Studio 2019\Projects\My Movies for WMC and CM 5.10\My Movies - Collection\Collection Management.vbine 609

File Attachment(s):
InstallerLog.txt (2kb) downloaded 0 time(s).

Hi,
This is a new installation with an empty database. I am getting the error when I click on „Synchronize“ to import the data from my online database. My collection is currently maintained through the iOS app on my iPad/iPhone.
Thanks again.