When you run a cloud service on development fabric, the development fabric uses a temporary folder to store files including local storage locations, cached binaries, configuration, diagnostics information and cached compiled web site content. By default this location is: C:\Users\<username>\AppData\Local\dftmp (Windows Azure Tools will periodically clean up this folder). Note: To manually clean, you can open an elevated Azure SDK Command Prompt and run: “csrun /devfabric:shutdown” followed by “csrun /devfabric:clean”. There’re some cases where length of the path can cause problems. This’ll give you following error message when you hit F5: “The path is too long after being fully qualified. Make sure the full path is less than 260 characters and the directory name is less than 248 characters.” To resolve: you could either rename those shorter, or change the location of development fabric temporary folder to be a shorter path. You can do this by setting _CSRUN_STATE_DIRECTORY to a shorter path, say “C:\A” for example. Make sure, you close Visual Studio and shutdown development fabric by using “csrun /devfabric:shutdown” command, or by clicking “exit” on Windows Azure tray icon.