If you build a snap with plus (+) in the snap name, the resulting snap file cannot be installed. $ snapcraft init Created snap/snapcraft.yaml. Edit the file to your liking or run `snapcraft` to get started $ cd snap/ $ ls snapcraft.yaml $ vi snapcraft.yaml Change the name of the snap to something with a plus. $ cat snapcraft.yaml name: snap+bug # you probably want to 'snapcraft register <name>' version: '0.1' # just for humans, typically '1.2+git' or '1.3.2' summary: Single-line elevator pitch for your amazing snap # 79 char long summary description: | This is my-snap's description. You have a paragraph or two to tell the most important story about your snap. Keep it under 100 words though, we live in tweetspace and your description wants to look good in the snap store. grade: devel # must be 'stable' to release into candidate/stable channels confinement: devmode # use 'strict' once you have the right plugs and slots parts: my-part: # See 'snapcraft plugins' plugin: nil $ snapcraft Preparing to pull my-part Pulling my-part Preparing to build my-part Building my-part Staging my-part Priming my-part Snapping 'snap+bug' | Snapped snap+bug_0.1_amd64.snap Try to install it. $ snap install --dangerous snap+bug_0.1_amd64.snap error: cannot read snap file: invalid snap name: "snap+bug"