MyConn.close есть    - но нет создания
Conn_Str присвоена - но не использована

if exists (select * from dbo.sysobjects where id = object_id(N'[dbo].[zaprosy]') and OBJECTPROPERTY(id, N'IsUserTable') =  1 )
drop table [dbo].[zaprosy]
GO

CREATE TABLE [dbo].[zaprosy] (
	[id_zapros] [int] IDENTITY ( 1 ,  1 ) NOT NULL ,
	[data] [datetime] NULL ,
	[is_sended] [bit] NULL ,
	[user_name] [nvarchar] ( 50 ) COLLATE Cyrillic_General_CI_AS NULL 
) ON [PRIMARY]
GO

ALTER TABLE [dbo].[zaprosy] WITH NOCHECK ADD 
	CONSTRAINT [PK_zaprosy] PRIMARY KEY  CLUSTERED 
	(
		[id_zapros]
	)  ON [PRIMARY] 
GO

Dim MyODBC As Workspace
Dim MyConn As Connection
Dim rstZapros As DAO.Recordset
Dim Conn_Str As String
Dim Sedd_String As String
Dim k As Variant
Set MyODBC = CreateWorkspace("", "admin", "", dbUseODBC)
MyODBC.BeginTrans
Conn_Str = "ODBC;DATABASE=workbase;UID=sa;PWD=;DSN=workbase"
Set MyConn = MyODBC.OpenConnection("", , , Conn_Str)
Sedd_String = "select * from zaprosy where is_sended=0 order by data"
Set rstZapros = MyConn.OpenRecordset(Sedd_String, dbOpenDynamic,  0 , dbPessimistic)
     rstZapros.AddNew
     rstZapros!Data = Date
     rstZapros!user_name = CurrentUser
     rstZapros.Update
    rstZapros.Close
  MyConn.Close
MyODBC.CommitTrans
MyODBC.Close