I downloaded the trial version of Folder Lock 5.3.5 and forgot my
password, now I can not uninstall it

This review may be helpful:

Cons: While the designers claim that the software cannot be deleted
without the password, this is certainly NOT the case. Opening the
uninstall icon in the program folder will tell you to open the program
and put the password in first, then uninstall using the menu option,
because it is not actually an uninstall script.

But the program can be easily uninstalled by simply selecting the
folder and pressing SHIFT + DELETE. This does not require a password,
and will delete the locker and all files contained therein.

http://www.download.com/Folder-Lock/3640-2092_4-10527751.html?pn=2&sb=3&v=0

Best regards,
Rainbow