Printing update query not working

[Crownknox]

The problem I have is this:
I like to print multiple invoices at the same time. To do this I have a yes/no field [tobeprinted] in [datatable1]. The query for the Invoice reports selects all records in the [datatable1] where the [tobeprinted]=False. So far, so good.

Next, I have a command button Print_Click on a form. When selected, the event procedure below is executed.
--------------------
DoCmd.RunCommand acCmdSaveRecord
DoCmd.SetWarnings False
DoCmd.OpenQuery "UpdateInvoicePartPrice", acNormal, acEdit
DoCmd.OpenReport "Invoice", acpRINT, "", ""
DoCmd.OpenQuery "updatePrintYes", acNormal, acEdit
DoCmd.RunCommand acCmdSaveRecord
End
-------------------
The Query "UpdateInvoicePartPrice" updates [invoiceprices].[partprice] from [itemlist].[unitprice] AND updates [InvoiceMain].[DateInvoiced]=Date().This is done from all records where [datatable1].[tobeprinted]=true This works great when only ONE recorded is selected to be printed. But returns the partprice to $0.00 if more that one record is selected.

Next it prints

And Finally it updates all records [tobeprinted]=No.

Why does the update not work right when more that one records [tobeprinted]=TRUE????????

This is a big problem for me.

Can anyone Help??????????

 

[braindead2]

Could you post the sql statements for the 2 querys then we can perhaps give better advice.

 

[Crownknox]

Here are the two queries
----------------------------
Query: UpdateInvoicePartPrice

UPDATE ShipperMain INNER JOIN InvoicePrices ON ShipperMain.ShipperNumber = InvoicePrices.ShipperNumber SET InvoicePrices.PartPrice = [unitprice], ShipperMain.Invoiced = Date()
WHERE (((ShipperMain.Print)=Yes));


Query: UpdatePrintYes

UPDATE ShipperMain SET ShipperMain.Print = No;
------------------------
Again, this works great when only one records (ShipperMain.Print)=Yes, but when more than one is yes it updates the unitprice to $0.00 instead of the correct price.