"accessing via the monitor" isn't really clear, but I assume you mean there's no icon in the taskbar to click on and they don't appear in the alt-tab cycle.
Sometimes this happens if the program can't fully open or fully close for some reason. Then it's kind of half present and half not present. If it's OK the next time, it's a one-time glitch. Don't care about it too much. If it's reproducable (also after a reboot) and doesn't happen on other PC's, there must be a cause, but it might be difficult to find.
And sometimes the program is designed to run in the background and not show anywhere. That's not an issue. Firefox certainly isn't such a program, but I don't know about ashampoo optimizer.
The best way I know of to solve Adobe issues is to use another pdf-viewer. Start with foxit reader (free download). I know nobody (but you might be an exception) who needs version 9 and can't use any other version of Adobe or other companies because of some feature that is unique to version 9.
several programs, like ashampoo optimizer & firefox show up as running in task manager but are not accessible via the monitor.
also adobe reader 9 continues to freeze on opened pdfs