I think you need to use a list box, and allow multi select, and then the user can select one or many of the parameters. You will also need to use two combo boxes, one to select the bottom of the range, like 1A, and one to select the top of the range, like 1Z, and then pass the parameters to your report.
For the top and bottom of the ranges, assuming you are running a report called "rptMyReport," try this:
Dim sStart As String
Dim sEnd As String
Dim sLink As String
Dim sDoc As String
sDoc = "rptMyReport"
sStart = Me.cboRangeStart
sEnd = Me.cboRangeEnd
sLink = "[Accnt_Code] Between '" & sStart & "' And '" & sEnd & "'"
DoCmd.OpenReport sDoc, acPreview, , , sLink
The sLink should be in the WHERE clause section of the DoCmd. line.
I can help with the code for a multi-select box if you need that. You should also validate entries in the combo boxes, and you should also use a cascading combo box so that when the user selects the start of the range, they are limited to the end of the range to only those items after the start of the range, to prevent 1C to 1A sort of entries.
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