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In my Programm i use ifstreams for file open and write functions.
But after i use a FileOpenDialog, istreams dont work anymore.
I think this is a bug in Irrlicht, i tried much to find the error in my code but it seems to be irrlichts mistake.
Probabilities are much more likely that you're not finding the files anymore due to the changed active directory. The file open dialog has the (not really good) behavior to change the current directory. Thus, you cannot access relative paths anymore as before.