To fix An error occurred while starting Roblox Studio, Studio details failed to create key or deploy, Reset your Router, Reset TCP-IP, Disable proxy settings, etc.

Fix #3: Update Roblox installation files. If Roblox is still showing the same crash error, the final solution that you can try is to update certain files in the installation folder.

If Roblox Marketplace is not working or loading and you see If you are having trouble loading Marketplace message, then see this post.