How to make run Counter Strike 1.6 on Windows 7.
Click on the Start button.
Use right-click Computer and then select Properties.
Click on to the Advanced System Settings.
Open the Performance Settings button, then click on to the Data Execution Prevention tab.
Check now the box named Turn on DEP for all the Programs and Services except those I select.
Now click Add and add game Counter Strike 1.6 in the list of exceptions.
See below on image this option :