Hi Dhanyalakshmi,
I've reviewed the crash you're experiencing with the toaster. Here are my responses to your last message to Marlon.
2. You mentioned that you want to build an image on Release `Yocto version=4.2 mickledore`, which is correct. However, in order to do so, you need to select the build system (4.2 mickledore) when creating a project, and then proceed to build the image. (Please refer to this [video](
https://www.youtube.com/watch?v=qYgDZ8YzV6w) for instructions on how to create a project in toaster and `select the desired build system (4.2 mickledore)`).
3. When attempting to reproduce the build crash you encountered, we followed the aforementioned steps. However, it appears that the image (`ls-image-main`) you are attempting to build does not exist in toaster under `Yocto version=4.2 mickledore`.