Problems passing a date from a form into Docmd.openreport - date

Question

I am pulling my hair out because I just don't see what is wrong here. I suspect it is a simple/stupid error but just can't see it. I am a relatively inexperienced VBA programmer but I like to think literate enough to get by with most programing langages.
Problem
I have a simple Invoicing system. One of the reports I want to be produced is a report of all the invoices issues after a specific date.
To that end I have created a report "All invoice query" which uses a query of the same name to generate a summary of all the invoices in the system and deliver a one line summary (date, amount, paid flag)
I wanted to amend this so that I can limit the printout to invoices after a particular date.
I created a field (text box; format shortdate) in my dashboard to hold the date and a button to 'run' the report
The button calls the procedure
Private Sub ButtonAfterDate_Click()
DoCmd.OpenReport "All invoice query", acViewPreview, , "[Invoice date] > #" & Me.Printdate & "#"
End Sub
This produces a report with all of the invoices in the system (i.e. no filtering)
If I go to the table where the data in held [Invoices] and copy the date from there and paste it into the form control the report starts working and the report only displays the invoices after the date.
I have checked that my form control is set to shortdate, I have tried typing the date and selecting it with a date picker (no difference still fails to filter)
In desperation I have tried changing the control to a list box that uses a query to lift the dates from the Invoice table (however that failed so went back to my original control button and field to hold the date (with date picker)
In summary
If I copy and paste a date from the table into the form control the OpenReport behaves as expects and filters
If I type the date or use the date picker to put the date in the form control OpenReport ignores any filtering and displays all the invoice summaries.
It seems like a data type problem but am at a loss what to try next
Thanks in advance for any help

Answer 1

I have found the answer. I didn't realise that the where clause of the Docmd.OpenReport must have any dates in US format i.e. mm/dd/yyyy I am in the uk and the localisation on windows (and indeed uk practice) enters this as dd/mm/yyyy
After doing some research I found a function to re-write the date from uk to us format then put the amended string in the where clause.
I found the code to modify the date here :http://bytes.com/topic/access/answers/511395-dates-where-clause
but for convienience:
Public Function FixDate(strDate As String)
Dim D1 As Integer, D2 As Integer
D1 = InStr(strDate, "/")
D2 = InStr(D1 + 1, strDate, "/")
FixDate = CDate(Mid(strDate, D1 + 1, D2 - (D1 + 1)) & "/" _
& Left(strDate, D1 - 1) & "/" _
& Mid(strDate, D2 + 1))
End Function
posted by Randy Harris
tech at promail dot com
I then modify my event procedure to use this code:
Private Sub ButtonAfterDate_Click()
Dim mydate As Date
mydate = Me.Printdate
FixDate (mydate)
DoCmd.OpenReport "All invoice query", acViewPreview, , "[Invoice date] > #" & mydate & "#"
End Sub
And it works!
Thanks to all those who looked and had a think about it and I hope that it helps someone else.