SysTools PDF Lock

Locking your PDF documents can ensure that no one but you can access them. As long as you remember the password, this added security measure can bolster both the security and privacy of the respective document: it’s an easy and effective way to safeguard it from prying eyes.

Securing multiple documents with a password can be a little cumbersome, however, which is where a tool like SysTools PDF Lock can assist you. Add your files in, configure the restrictions and password you wish to apply, and all should be handled by the software within seconds.

As stated earlier, it’s not that securing multiple PDF files with a password is necessarily difficult, but that it’s a rather awkward menial task that a piece of software can carry out for you. This PDF locking tool is straightforward and functional in both form and function, as it really doesn’t take you long to figure out how to use it.

You can add as many files as you like, but do note that the Free version will only lock the first 2 and apply a watermark on output. I feel that the watermark is of the more intrusive kind.

Aside from securing your documents with a password and your desired encryption method — of which there are four available ones — there’s also the possibility to apply printing and modification restrictions.

To put it simply, you can disable printing, or just limit it to a lower resolution. As for restricting modifications, you can disable inserting, deleting, or rotating pages, deactivate filling and signing, or prohibit extracting pages. Of course, you may also deny changes altogether. Once put in place, a password will be required to bypass these limitations.

SysTools PDF Lock is a functional piece of software that can lock multiple PDF documents within seconds. While the program is decent at what it does, I wouldn’t necessarily recommend it to Free users due to the intrusive watermark that is applied in the Demo version.