I have Windows 7 Ultimate 64-bit, and never had any problem installing 64-bit programs.
Now, when a try to install any 64-bit programs it shows a message of incompatible version of the program with the running Windows, but my Windows 7 is 64 bits.
I really don't know what to do, and any help would be appreciated.
Program may be old and than u can try to use the compatibility mode.
Run the Program Compatibility Wizard
Open the Program Compatibility Wizard by clicking the Start button , clicking Control Panel, clicking Programs, and then clicking Use an older program with this version of Windows.
Follow the instructions in the wizard.
If you cannot install a program, insert the installation disc for the program and, using the wizard, browse to the program's setup file, usually called Setup.exe, Install.exe, or something similar. The wizard is not designed to work on programs that have an .msi file name extension.
To change compatibility settings manually for a program, right-click the icon for the program, click Properties, and then click the Compatibility tab.