Timeout al momento de generar la planilla

Al momento de generar la planilla, a veces se logra generar correctamente y a veces la barra de estado no se mueve (a pesar de que internamente la planilla se logra generar)

A veces en la bitacora aparece este mensaje

Cabe mencionar que en el servidor de base de datos no hay otras bases de datos mas que las propias de Evolution

System.Data.EntityException: The underlying provider failed on Open. ---> 
System.InvalidOperationException: Timeout expired.
The timeout period elapsed prior to obtaining a connection from the pool.
This may have occurred because all pooled connections were in use and max pool size was reached.
at System.Data.ProviderBase.DbConnectionFactory.GetConnection(DbConnection owningConnection)
at System.Data.ProviderBase.DbConnectionClosed.OpenConnection(DbConnection outerConnection, DbConnectionFactory connectionFactory)
at System.Data.SqlClient.SqlConnection.Open()
at System.Data.EntityClient.EntityConnection.OpenStoreConnectionIf(Boolean openCondition, DbConnection storeConnectionToOpen, DbConnection originalConnection, String exceptionCode, String attemptedOperation, Boolean& closeStoreConnectionOnFailure)     --- End of inner exception stack trace ---
at System.Data.EntityClient.EntityConnection.OpenStoreConnectionIf(Boolean openCondition, DbConnection storeConnectionToOpen, DbConnection originalConnection, String exceptionCode, String attemptedOperation, Boolean& closeStoreConnectionOnFailure)
at System.Data.EntityClient.EntityConnection.Open()
at System.Data.Objects.ObjectContext.EnsureConnection()
at System.Data.Objects.ObjectQuery`1.GetResults(Nullable`1 forMergeOption)
at System.Data.Objects.ObjectQuery`1.System.Collections.Generic.IEnumerable<T>.GetEnumerator()
at System.Linq.Enumerable.FirstOrDefault[TSource](IEnumerable`1 source)
at System.Data.Objects.ELinq.ObjectQueryProvider.<GetElementFunction>b__1[TResult](IEnumerable`1 sequence)
at System.Data.Objects.ELinq.ObjectQueryProvider.ExecuteSingle[TResult](IEnumerable`1 query, Expression queryRoot)
at System.Data.Objects.ELinq.ObjectQueryProvider.System.Linq.IQueryProvider.Execute[S](Expression expression)
at System.Linq.Queryable.FirstOrDefault[TSource](IQueryable`1 source, Expression`1 predicate)
at Aseinfo.VH4.WindowsServices.Salarios.Ejecutores.EjecutorFormulacionBase.GenerarPlanilla(IGenericEntityRepository entityRepository, PeriodoPlanillaEnGeneracion periodoPlanillaEnGeneracion, ThreadsData threadsData) in c:\BuildAgent\work\608d469cc106b504\VH4\WindowsServices\GeneraPlanillaWindowsService\Salarios\Ejecutores\EjecutorFormulacionBase.cs:line 297