Is e: a network drive? If so try putting the images local to see if that makes a difference.

If that's the problem you need to add a .config file setting to allow network access to resources (and dll loading).

http://www.west-wind.com/webconnection/docs/?page=_36e0qlogr.htm

The topic mentions DLL loading but I think the same thing applies to any resources accessed cross the network. This setting basically makes a .NET application behave like a 'normal' Windows application without dealing with security policies.

Actually, e: is a local drive on my machine. But I finally solved my problem by debugging the code in Visual studio first. This is what I finally got working:

loForm = loStamper.AcroFields
loCmd = loBridge.InvokeMethod(loForm, "GetNewPushbuttonFromField", "cmdSignature")
loCmd.Image = loBridge.InvokeStaticMethod("iTextSharp.text.Image", "GetInstance", "E:\Marcia\MGASig.tif")
loCmd.Layout = 2
loCmd.ProportionalIcon = .T.
loCmd.BorderWidth = 0
loCmd.Visibility = 0
loBridge.InvokeMethod(loForm, "ReplacePushbuttonField", "cmdSignature", loCmd.Field)
loBridge.InvokeMethod(loForm, "RenameField", "cmdSignature", "cmdActualSignature")

Thanks so much for wwDotNetBridge! It sure has made my life a lot easier!