RestService with devart dotConnect for Oracle loses License information

Question

We have a Rest Service (Asp.net MVC .net 4.7.1 / Asp.net Core) using Devart dotConnect for Oracle (Version 9.6.646.0.).

Here occurs a strange phenomenon: After some time running fine (this may be after half an hour until some hours) the Services using database access throw a devart licencing exception (License not found)

After re-publishing the same sources, everything runs fine - again for some time. This phenomenon is the same for .net 4.7.1 and .net Core Services.

Restarting the site in IIS or restart IIS does not help.

We have embedded the license information in a licenses.config and licenses.lixc file

Licenses.licx:

Devart.Data.Oracle.OracleConnection, Devart.Data.Oracle, Version=9.6.646.0, Culture=neutral, PublicKeyToken=09af7300eec23701

Licenses.config:

KVSH.KVRest.ERP.WebApi.WebHost

Server: Windows Server 2012 R2 (devart dotConnect not installed)

IIS: Version 8.5.9600

Does anyone have an idea?

This is the exception:

 System.Data.Entity.Core.ProviderIncompatibleException: An error occurred accessing the database.
 This usually means that the connection to the database failed. Check that the connection string 
is correct and that the appropriate DbContext constructor is being used to specify it or find it 
in the application's config file. See http://go.microsoft.com/fwlink/?LinkId=386386 for 
information on DbContext and connections. See the inner exception for details of the failure. 
---> System.Data.Entity.Core.ProviderIncompatibleException: The provider did not return a ProviderManifestToken string. 
---> Devart.Data.Oracle.OracleException: License not found. Please view "Licensing" topic 
in dotConnect for Oracle documentation for details or contact Devart technical support.
   bei Devart.Data.Oracle.OracleConnection.Open()
   bei Devart.Data.Oracle.Entity.ap.a(DbConnection A_0, OracleServerType& A_1, Nullable`1& A_2)
   bei Devart.Data.Oracle.Entity.ap.b(DbConnection A_0)
   bei Devart.Data.Oracle.Entity.OracleEntityProviderServices.GetDbProviderManifestToken(DbConnection connection)
   bei System.Data.Entity.Core.Common.DbProviderServices.GetProviderManifestToken(DbConnection connection)
   --- Ende der internen Ausnahmestapelüberwachung ---
   bei System.Data.Entity.Core.Common.DbProviderServices.GetProviderManifestToken(DbConnection connection)
   bei 
System.Data.Entity.Utilities.DbProviderServicesExtensions.GetProviderManifestTokenChecked(DbProviderServices providerServices, DbConnection connection)
   --- Ende der internen Ausnahmestapelüberwachung ---

Answer 1

This phenomenon is the same for .net 4.7.1 and .net Core Services.

There are two sets of the provider assemblies with different licensing approaches:

• .NET Framework -> https://www.devart.com/dotconnect/oracle/docs/?licensing.html
• .NET Standard (.NET Core) -> https://www.devart.com/dotconnect/oracle/docs/?licensingstandard.html

There should not be the same error.

IIS: Version 8.5.9600 Licenses.config: KVSH.KVRest.ERP.WebApi.WebHost

Please add w3wp.exe to your Licenses.config because that is the name of IIS process.

We cannot reproduce the error in our environment. If the upgrade to v9.11.1064 in production doesn't help, give us the following information via https://www.devart.com/company/contactform.html:

a) check logs of your Windows and IIS in production. Is there some event (Windows Upgrade, IIS error, etc) that precedes the license error?

b) describe the Application Pool used by your application in IIS

c) describe your application: its target framework, web application (precompiled) or web site (compiled on demand), version of EF6 (6.4, etc)

d) specify your connection string (mark confidential information with asterisks)