incorrect syntax after server up for a few days

Dear All,

My VB.Net application connects to MSSQL. It is always running fine for a few days, but encounters "incorrect syntax" as following unless the server is restarted.

--
Exception occurred System.Runtime.InteropServices.COMException (0x80040E14): Line 1: incorrect syntax near 'CDO'.
at ADODB.ConnectionClass.Execute (String CommandText, Object& RecordsAffected, Int32 Options)
--

There are a few applications in the server. If certain service is stopped, my program continues to run. So I am sure that the MSSQL connections have been taken up, which causes the error. How to prove it? And is there any way to reserve some DB connections to a particular application only?

Thanks for any hint!

I attach my codes below. Anything wrong with the way that I handled the ADODB?

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Public Sub SendAllEmails()
Try
Dim cn As ADODB.Connection = openConn()
Dim rs As ADODB._Recordset
Dim rs2 As ADODB._Recordset
sqlstmt = "select * FROM EMAILTABLE"
rs = cn.Execute(sqlstmt)

While Not rs.EOF

Dim MAIL_ADD_USED As String = rs.Fields("MAIL_ADD_USED").Value.ToString

sqlstmt = "select * from NAMETABLE where EMAIL = '" & MAIL_ADD & "'"
rs2 = cn.Execute(sqlstmt)

If Not rs2.EOF And ErrMsg = "" Then

ErrMsg = SendMail(MAIL_ADD, REPORT_TITLE)

If Not ErrMsg Is Nothing And ErrMsg.Equals("Success") Then
MAIL_DATE_SENT = Now.ToString
MAIL_STATUS = "S"

'wait to make sure the email is sent
System.Threading.Thread.Sleep(1000 * 30)
Else
MAIL_STATUS = "F"
End If

End If

rs2.Close()

sqlstmt = "update EMAILTABLE set " & _
" MAIL_STATUS = " & MAIL_STATUS & "," & _
" MAIL_ERRMSG = null" & _
" where EMAIL = " & MAIL_ADD

cn.Execute(sqlstmt)

rs.MoveNext()

End While

rs.Close()
cn.Close()

Catch e As Exception
EventLog1.WriteEntry("Exception: " & e.ToString)
End Try

End Sub
----------------------Dear All,

My VB.Net application connects to MSSQL. It is always running fine for a few days, but encounters "incorrect syntax" as following unless the server is restarted.

--

Are you using VB.Net? Then how come Recordset come into existence...:S
See the BOL to use VB.net (ADO.Net)|||Well I took over the codes from the programmer. vb.net is quite new to me. thanks for the hint but is there any sample about how to make use of ado.net?

Actually I am more keen to know whether the MSSQL connection can be released and allocated by DBA. There are othere applications that I simply have no control.

Thanks.|||Well I took over the codes from the programmer. vb.net is quite new to me. thanks for the hint but is there any sample about how to make use of ado.net?

Actually I am more keen to know whether the MSSQL connection can be released and allocated by DBA. There are othere applications that I simply have no control.

Thanks.

Check these...
sending mail (http://www.c-sharpcorner.com/UploadFile/sushmita_kumari/SendingMail101062006054220AM/SendingMail1.aspx?ArticleID=91ece6d8-eaaf-41ab-ac6f-533dc215eacf)

Ado.net stored proc use (http://aspalliance.com/673_CodeSnip_Calling_a_Stored_Procedure_from_ASPNE T_20)

All about Ado.net (http://aspalliance.com/articles/LearnADONET.aspx)

And you can always use Profiler to check the status of your server.And to kill process check this
Kill Process (http://msdn2.microsoft.com/en-us/library/ms173730.aspx)