Problem Loading default B747-400

I am having a strange problem that so far i can not figure out
When ever I try to select the default B747-400 FS stops responding I have checked all other aircraft I have and this and one other B747-300 are the only ones that I can not select they come up in the window showing them but when you press ok the game stops responding and I have to end the task. I tried replace the default B747 with the one off of the disk1 and no luck. I also renamed the original FS9 cfg file and let it build a new one no luuck there. I am not sure when the last time was that they worked I rember changing a program that altered the view you see when in the select aircraft screen I do not remember if I used the B747s after that. I wonder if that is my problem ???
Has anyone else ran across this problem :(

Has anyone else ran across this problem :(