MEDLIGHT is classified as Win32:PUP-gen (potentially unwanted program).
What is PUP?
PUP is crapware. MEDLIGHT have several types of unwanted behaviour:

1. Displaying popup ads.
2. Hijacking your browser.
3. Infecting your desktop shortcuts, etc.
4. Inserting ads to the web pages.

MEDLIGHT can redirect your browser search, collect your personal information and sell it for advertising.
MEDLIGHT is usually hard in removing. Some people could not find uninstall program for MEDLIGHT in the Control Panel.
Sometimes MEDLIGHT uninstaller does not work.

How MEDLIGHT got on my computer?

Usually you got MEDLIGHT with as part of a bundle with another tool you downloaded from the Internet. Since MEDLIGHT manufacturer pays software developers for distributing MEDLIGHT within their applications, MEDLIGHT is often included as part of the installer.
Usually, you have not only one MEDLIGHT problem, but a bunch of similar WIN32:PUPs.

How to remove MEDLIGHT?

Step-by-step Guide for manual removal of MEDLIGHT:

1. Uninstall MEDLIGHT using Windows uninstallation applet (use Add/Remove Programs or Uninstall Program or Apps & features).
2. Open Task Manager to kill all "MEDLIGHT" related processes.
3. Use Windows search to find and remove "MEDLIGHT" files and folders.
4. Run services.msc to disable a "MEDLIGHT" Windows service.
5. Execute taskschd.msc to get rid of "MEDLIGHT" scheduled tasks.
6. Open regedit.exe and delete MEDLIGHT registry keys and values.
7. Check your shortcuts on your desktop and in the Start menu for MEDLIGHT presence. Fix infected shortcuts.
8. Remove a virus from Google Chrome.
9. Remove a virus from Internet Explorer.
10. Remove a virus from Mozilla Firefox.
11. Clean your Recycle bin and temporary files.