Option Compare Database
Option Explicit

Public Function SetProperties(strPropName As String, _
varPropType As Variant, varPropValue As Variant) As Integer

    On Error GoTo Err_SetProperties

    Dim db As DAO.Database, prp As DAO.Property

    Set db = CurrentDb
    db.Properties(strPropName) = varPropValue
    SetProperties = True
    Set db = Nothing

Exit_SetProperties:
    Exit Function

Err_SetProperties:
    If Err = 3270 Then    'Property not found
        Set prp = db.CreateProperty(strPropName, varPropType, varPropValue)
        db.Properties.Append prp
        Resume Next
    Else
        SetProperties = False
        MsgBox "SetProperties", Err.Number, Err.Description
        Resume Exit_SetProperties
    End If
End Function