.

If you double click to open the program and nothing happens then the reason that the program may not load is:

DEP (data execution prevention) a security feature in Windows.
Right click My Computer and choose properties. Select the Advanced tab and
click the Settings pushbutton for the Performance section. Select the Data
Execution Prevention tab. If the radio-button is selected for "Turn on DEP
for all programs and services except those I select" then you need to add
the db55run.exe to the list.

OR ... If you receive the error message: 

Then a "Windows" System File has been removed from your computer.  This Windows System file is called "autoexec.nt" and it belongs in the c:\windows\system32 folder.  This file "autoexec.nt" gets removed due to spyware.  There are a couple of things you need to do.

1) Remove the spyware
2) Put the "autoexec.nt" file back on your computer.

We can help you with both.

1) Go to www.lavasoftusa.com and download "Adaware SE Personal".  Download, then install and run this program.  There is no charge to use this program and it is recognized by the computer industry as one of the best and safest programs to remove spyware.

Or - go to www.safer-networking.org/en/download/ and download "Spybot Search & Destroy".    Download, then install and run this program.  There is no charge to use this program and it is recognized by the computer industry as one of the best and safest programs to remove spyware.

Both of these programs are very very good at removing spyware from your computer.  There are other spyware removal programs out there "and fake spyware removal programs that are actually spyware themselves".  Don't be tricked.  I recommend using the industry standard well known programs "Adaware or Spybot S & D" - they are safe and they work!  Visit www.cnet.com for reviews on these programs.

2) Next you need to put your "autoexec.nt" file back on your computer.  Use the following small self extracting utility program to put it back.  You may want to back up your system first.  Maplesoft will not be responsible for any problems you may encounter on your computer.  Click on:
AUTOEXEC.NT.EXE
and download and run this program to put the "autoexec.nt" file back into the c:\windows\system32 folder.

Note: To keep from getting spyware in the future, regularly run either Adaware or Spybot S & D once a month or so.  We also recommend that you visit www.mozilla.org and download Firefox to use as your webbrowser and Thunderbird as your email client.  Firefox "in my opinion" is faster and safer than Internet Explorer.  You'll get far less spyware!  And thunderbird by nature will help remove the possiblity of receiving a virus.  If you don't have an antivirus program "then you need one".  Go to www.grisoft.com and download the free version of "AVG" for your antivirus protection.  Keep it up to date - it's important.  Make sure you have the Windows Firewall on and keep your computer up to date with Security Patches from Microsoft.

If you need help - email:  support@maplesoft.net