Use a string variable to hold your SELECT statement. After you overcome the quoting issues so you can create a valid string in VBA, then use that variable with OpenRecordset.
For example, if the datatypes of your groupNum and DateClosed fields are both text ...
Dim strSelect As String
strSelect = "Select * from tblActionLog Where groupNum ='" & _
Me.txtGroupNr.Value & "' And DateClosed < '1/1/1900'"
Debug.Print strSelect '<-- Ctrl+g to go to Immediate window and see the statement text
Set rsCanCounter = db.OpenRecordset(strSelect, dbOpenDynaset)
If DateClosed is Date/Time datatype, use # instead of quotes to delimit the date value:
strSelect = "Select * from tblActionLog Where groupNum ='" & _
Me.txtGroupNr.Value & "' And DateClosed < #1900-1-1#"