Retired Solution Unsupported Version: Data Load Service Error - Exception Message: -2 : Timeout e (4260080)

AfterMail Data Load Service crashes below error in application log while proceeding large mailboxes:

Exception Source: AfterMail Data Load Service
Exception Type: System.Exception
Exception Message: -2 : Timeout expired. The timeout period elapsed prior to completion of the operation or the server is not responding.
Exception Target Site: Select
(Inner Exception)
Exception Source: .Net SqlClient Data Provider
Exception Type: System.Data.SqlClient.SqlException
Exception Message: Timeout expired. The timeout period elapsed prior to completion of the operation or the server is not responding.
Exception Target Site: ExecuteReader
Date and Time: dd.mm.yyyy hh:mm:ss
Machine Name: xxx
IP Address: xx.xx.xx.xx
Current User: DomainName\ArchiveMgr_Journal
CLR Version: 1.1.4322.2300
Platform (version): Win32NT (5.2.3790.0)
Application Domain: Archive Manager Data Load Service.exe
Assembly Codebase: file:///C:/Program Files/ArchiveManager/Archive Manager Data Load Service.exe
Assembly Fullname: AfterMail Data Load Service, Version=3.7.0.459, Culture=neutral, PublicKeyToken=null
Assembly Version: 3.7.0.459
Exception Source: .Net SqlClient Data Provider
Exception Type: System.Data.SqlClient.SqlException
Exception Message: Timeout expired. The timeout period elapsed prior to completion of the operation or the server is not responding.
Exception Target Site: ExecuteReader

---- Stack Trace ----
at System.Data.SqlClient.SqlCommand.ExecuteReader(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream)
at System.Data.SqlClient.SqlCommand.ExecuteScalar()
at xbec8ef5abc6424a1.x6d683e3089a43813.x9f27f896f05e0d04(SqlTransaction x1307652248026bc8, SqlCommand xc51da2e32df1a82c)
at AfterMail.BusinessLayer.Message.Select(Guid x1b0f6ab9aa137aed, SqlTransaction x66e05d6918635530)

(Outer Exception)