ArcPy gives error Object: CreateObject cannot open map document?

Question

This should be a really simple process but I am having issues. I want to search a workspace for all files with a certain string and then add them to the current workspace with a selected symbology.

Issues:

1. Error [[: Object: CreateObject cannot open map document]] I have to set the map doc to be the current workspace
2. When run in the python window the symbology is not updated.
3. It should only update the map frame/toc once everything is added

Code:

import os, arcpy, arcpy.mapping
from arcpy import env

GDB = arcpy.GetParameterAsText(0)
Text = arcpy.GetParameterAsText(1)
symbologyLayer = arcpy.GetParameterAsText(2)
#OutputGDB = arcpy.GetParameterAsText(3)

arcpy.env.workspace=GDB
mxd=arcpy.mapping.MapDocument("CURRENT")
list=arcpy.ListFeatureClasses('*'+Text+'*')

for layer in list:
    dataFrame = arcpy.mapping.ListDataFrames(mxd, "Layers")[0]
    addLayer = arcpy.mapping.Layer(layer)
    arcpy.mapping.AddLayer(dataFrame, addLayer, "BOTTOM")
    arcpy.ApplySymbologyFromLayer_management (addLayer, symbologyLayer)

# Clean up the MapDocument object by deleting it
#del mxd

arcpy.RefreshActiveView()
arcpy.RefreshTOC()

ERROR DETAILS

Messages

Executing: ProcessDatasets22 P:\2012\Job_044_DM_Radio_Propogation\Working\FinalPropogation\cb_BEL07\working\bel07.gdb _dow P:\2012\Job_044_DM_Radio_Propogation\Working\signal_strength_poly.lyr Start Time: Mon Mar 19 14:11:27 2012 Running script ProcessDatasets22... : Object: CreateObject cannot open map document Failed to execute (ProcessDatasets22). Failed at Mon Mar 19 14:11:27 2012 (Elapsed Time: 0.00 seconds)

Answer 1

found the answer -it has to run in the foreground and can not be in the background or from a catalog session.

Answer 2

I think the problem may be that you need the keyword for the current workspace to be set to "CURRENT" (as per the documentation's example code) not "Current".

Also, as an aside you appear to have this line of code (still needs CURRENT to be put in) twice:

mxd=arcpy.mapping.MapDocument("Current")

Something else that seems astray is that you are treating your list of feature classes as if they are layers. For example, the Layer object expects layers from either an *.mxd or a *.lyr but you are feeding it feature classes. I'm thinking that you should use MakeFeatureLayer_management on your feature classes first.