Updating Records in .txt file

Private Sub btnUpdate_Click()

Const adCmdText = &H1
Dim i As Long, j As Long
Dim MyWorkbook As Workbook

Dim datConnectiontxt As ADODB.Connection
Dim recSetxt As ADODB.Recordset
Dim strDBtxt, strSQLtxt, strSQLtxt2 As String

'I compare the data from the query against the data of a OWC Spreadsheet
Dim spsUSheet As OWC10.Worksheet
Set spsUSheet = spsUsers.Worksheets(1)

Set MyWorkbook = ThisWorkbook
Set datConnectiontxt = New ADODB.Connection
Set recSetxt = New ADODB.Recordset

'Since this is an app for VBA (Excel), the Users.txt file (DataBase) is in the 
'same location
strDBtxt = MyWorkbook.Path  
strSQLtxt = "SELECT * FROM Users.txt WHERE [Description] = 'Unknown';"

datConnectiontxt.Open "Provider=Microsoft.Jet.OLEDB.4.0;" & _
		  "Data Source=" & strDBtxt & ";" & _
		  "Extended Properties=""text;HDR=YES;FMT=FixedLenght"""

recSetxt.Open strSQLtxt, datConnectiontxt, adOpenForwardOnly, adLockReadOnly, adCmdText 


For i = 2 To spsUSheet.Range("a1").End(xlDown).Row
If IsEmpty(spsUSheet.Cells(i, 2).Value) Or IsNull(spsUSheet.Cells(i, 2).Value) GoTo Sig
End If
'In the line below occurs the error
strSQLtxt2 = "UPDATE Users.txt SET [Description] = " & spsUSheet.Cells(i, 2).Value _
		   & " WHERE [UserID] = " & spsUSheet.Cells(i, 1).Value & ";"
datConnectiontxt.Execute strSQLtxt2
Sig:
Next i

closefrmUsers
End Sub