My .Net program based on the ArcEngine 10 SDK will not run on other computers. I wrote a simple program that just performs the license check with "ProductCode.EngineOrDesktop" and then when a button is pressed it attempts to load each of the 4 main controls, the AxToolbarControl, AxTOCControl, AxMapControl, and the AxPageLayoutControl. On every machine around it fails with "You must have a license to use this ActiveX control." except my development machine. The license check always suceeds but loading a control always fails. This is true whether the machine has the runtime installed or the actual Desktop product. Does the ArcEngine SDK even work? I've found reports of this error on the forums and none of the suggested resolutions work for me. Has anyone been able to use this SDK to distribute something? I installed service pack 3 and it just broke pieces of my code and ESRI response was to tell me my code was wrong tho they have yet to offer an alternative. I'd just like to copy this simple program to a machine, run the Runtime Engine install and then run the program. Is that too much to ask? I set all ArcGIS references to "Specific Version = False." I set the license check to run for Engine or Desktop and report failure (it doesn't.) I dynamically instantiate a control and add it to a panel. All of this works fine on one machine and fails on every other despite the license check suceeding. Is there an ESRI program available that will scan a machine and indicate whether it is correctly set up? Is there any help for this or must I just throw my error into the bitbucket of support and wait?