Can't Edit an EXCEL Worksheet!!!!!!

[bhuts]

Hi!
As a newcomer to VB,I face the following problem:

NAME IDNO AGE SEX
aaa 24 male
bb male
aaaa 678
cc 434 23
mujje 2222 21 male
(The alignment of the entries might get distorted after I post it)
My EXCEL WORKSHEET(which is obtained from another application) contains data as shown above.After I display a record (in combo box and text boxes)for which entries are incomplete(say,for cc)and try to complete the entries(here for cc it's SEX) I get ERROR:
"DATA TYPE CONVERSION ERROR"
(textsex.text="some text I put",data1.recordset.fields (SEX)=Null)
How to get rid of this????
CODE for displaying records:
Data1.Recordset.MoveFirst
While Not Data1.Recordset.EOF
If ComboNAME.Text = Data2.Recordset.Fields(NAME) Then
TextIDNO.Text = Data2.Recordset.Fields(IDNO) & ""
TextAGE.Text = Data2.Recordset.Fields(AGE) & ""
TextSEX.Text = Data2.Recordset.Fields(SEX) & ""
Exit Sub
Else
Data1.Recordset.MoveNext
End If
Wend

CODE for editing records:
Data1.Recordset.Edit
If ComboNAME.Text = Data1.Recordset.Fields(NAME) Then
Data1.Recordset.Fields(IDNO) = TextIDNO.Text
Data1.Recordset.Fields(AGE) = TextAGE.Text
Data1.Recordset.Fields(SEX) = TextSEX.Text
Data1.Recordset.Update
End If

(NAME displayed in the combo box is NOT EDITABLE).
PLEASE SHOW ME SOME WAY OUT......