Have you ever tried to open previously created GNS3 projects and topology files which their used IOS image files had different paths? Sometimes you receive a project folder from a friend to check a problem or simulate a situation they have experienced at work. At the very begining, when just opening the file, you will receive the following error message:
This error causes GNS3 to suddenly stop opening the project. But the solution is simple, as easy as eating a cake. 🙂 Just open the topology.net file in Notepad and correct the IOS path.
Now you can open your project without any problems and go ahead.
This seems to be due to a bug in the application and unfortunately exists in version 0.8.2.
Persiance 