You will receive an error message at the point of installing DESlock+ if you have selected the wrong version for your operating system. If you are unsure of which bit operating system you are running, please see this knowledge base article: KB107 - Should I download a 32-bit or 64-bit version of DESlock+?

There are two different versions of DESlock+, a 32 bit and a 64 bit. The version which you install must correspond to the operating system you are using. 

If you are trying to install the 32bit version of DESlock+ on your 64bit operating system the message "Error: This installation does not support DESlock+ under 64bit Windows."

If however you are installing a 64bit version of DESlock+ on a 32bit operating system, you will see the message "This installation package is not supported by this process type.  Contact your product vendor."