Hey ,
I have a question , if i surf on the web with the sandbox of avast.
Can i visit any site i want ?
If i stumble upon a nasty exploit , nothing will happen ?
In theory, nothing would get out of the sandbox if you set the most rigid options (not saving/preserving any file or registry for addons, extensions, plugins, etc.).
That rather depends on what avast version you have, only the avast pro and AIS versions have the full sandbox (not just the autosandbox).
If you have the full sandbox then you can elect to run your browser sandboxed.
Since you now have over 20 posts, you could include a profile signature, giving some information on your system, especially avast version. This information allows us to more precise information/help.