ShareAlarm

ShareAlarm is a small and portable software application that pops up notifications every time a remote computer attempts to access your shared folders. It targets all types of users, regardless of their skill level.
Since installation is not a prerequisite, you can simply drop the executable file anywhere on the hard drive and run it.
As an alternative, you can save ShareAlarm to a USB flash drive or similar removable device, and run it on any computer without installing anything beforehand.
What should be mentioned is that Windows Registry does not get entry updates, and files are not left behind on the hard drive when removing the tool.
The interface of ShareAlarm is based on a standard window with a well-organized layout, where you can view the name, user name, path and operating system for each workstation that's trying to get a glimpse of your shared folders.
You can select a WAV or MP3 file from the computer to assign it as a sound notifier, as well as test the alarm and stop it. In addition, you can block a workstation's access through the context menu, create a black list, as well as close a session.
ShareAlarm barely uses CPU and system memory, so it doesn't burden the computer's overall performance. It has a good response time and works fine, without making the operating system hang, crash or pop up error dialogs; we haven't encountered any issues in our tests.
On the downside, the program has not been updated for a very long time, hence it is not supported by newer operating systems. Other than that, ShareAlarm can be seamlessly handled, even by inexperienced users.