Why do I get "Unfortunately an error occurred" in a PrinterOrder.com admin window when opening another PrinterOrder.com window?
Printerorder.com uses session cookies to keep track of what user is using the system. This is true regardless of whether you are logging in as an administrator to make changes, or as a non-privileged user to see the changes, or not logging in at all to see an Online Store view. When you open up another tab in your browser to connect as a non-privileged user, a new session cookie is sent to your browser. This replaces the session cookie that was being used for your administrative view. Therefore, the administrative session becomes invalid and you cannot proceed without re-logging in.
As little as clicking a link from an email notification can start a new session (and invalidate existing ones), because a new session is created even if you do not log in.
The size of this problem and the workaround depends on what browser you are using. With Internet Explorer, opening a new window (rather than a new tab) forces the session cookies to be kept separate. With Firefox, session cookies are shared across all windows; the only way to keep sessions separate is to start another instance of firefox using a new profile. We are currently investigating other browsers.
Another workaround is to use different browsers for each session. For example, use Firefox for the administrative session and Internet Explorer for the non-privileged session.