DirectoryEntry fails when Published on IIS

Hello!

I have an web application that changes the user's password on Active Directory using the object DirectoryEntry.
When I run the application on VisualStudio it works perfectly, but when I publish on IIS it doesn't work.
But I don't have an error message or something like this, because the only error that occurs is that the method ( directoryEntry.Invoke("ChangePassword", new object[] { oldPassword, newPassword }); ) always goes to CATCH on the try catch.

May someone help me, please??
There is a long time that I'm try to do this...

Thanks!!!

Phillipe.

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