I have a form based on a tablea.
The form has a tabcontrol with 6 tabs. On each tab is a form that is based 
on different tables, tablea, tableb, tablec, tabled, tablee, tablef. Each 
form on each tab has a control based on the field codenbr in each table.
All the tables are linked on a control whose field  has the same name in 
each table, codenbr.
There is a control, codenbr, on my main form where I input a new record in 
tablea and as I open each tab control a record is created in the other 
tables and the value of each codenbr is populated with the value from my 
main form.
On two of the tabs as the record is created in their forms there is also an 
index created called hindex and vindex in the two tables table c and tablef. 
These are needed to link these tables to other tables in the database that 
are not on this particular form. The indexes are consecutive numbers in 
Autonumber fields and are the primary keys of the two tables in question.
However as soon as I input any data into my main form I get an error message 
to say that the Automation ID is not available. Obviously there is a problem 
with the Autonumbering of these index fields.
Can I achieve the same end with the DMax function to automatically create 
the consecutive values for each hindex and vindex ?
I'm using Access 2003
Hope I've explained that, would really appreciate some help.
Thanks
Tony 

On Mon, 13 Aug 2007 17:04:27 +0100, "Tony Williams" <tw@invalid.com> wrote:

> I get an error message 
>to say that the Automation ID is not available. Obviously there is a problem 
>with the Autonumbering of these index fields.

That's not obvious to me, at all. An Autonumber does not typically have the
name "Automation ID". Did *you* assign that fieldname to some field in one or
more of your tables? If not, I strongly suspect that there is some completely
unrelated problem with your code or with the database.

>Can I achieve the same end with the DMax function to automatically create 
>the consecutive values for each hindex and vindex ?

Yes, using the form's Beforeinsert event:

Private Sub Form_BeforeInsert(Cancel as Integer)
Me!hindex = NZ(DMax("[hindex]", "[tablename]")) + 1
End Sub

but I fear that this will leave the (autonumber-unrelated) Automation ID
problem unaffected.

             John W. Vinson [MVP]

Thanks John I'll try that.
Tony
"John W. Vinson" <jvinson@STOP_SPAM.WysardOfInfo.com> wrote in message 
news:3as1c35h7pja1f9fe9vildsdn4hrt36thj@4ax.com...
> On Mon, 13 Aug 2007 17:04:27 +0100, "Tony Williams" <tw@invalid.com> 
> wrote:
>
>> I get an error message
>>to say that the Automation ID is not available. Obviously there is a 
>>problem
>>with the Autonumbering of these index fields.
>
> That's not obvious to me, at all. An Autonumber does not typically have 
> the
> name "Automation ID". Did *you* assign that fieldname to some field in one 
> or
> more of your tables? If not, I strongly suspect that there is some 
> completely
> unrelated problem with your code or with the database.
>
>>Can I achieve the same end with the DMax function to automatically create
>>the consecutive values for each hindex and vindex ?
>
> Yes, using the form's Beforeinsert event:
>
> Private Sub Form_BeforeInsert(Cancel as Integer)
> Me!hindex = NZ(DMax("[hindex]", "[tablename]")) + 1
> End Sub
>
> but I fear that this will leave the (autonumber-unrelated) Automation ID
> problem unaffected.
>
>             John W. Vinson [MVP]