Foxit reader and Adobe reader both are free PDF Readers to view PDF files.If you are using both Adobe reader and Foxit reader for some reason and if you want to set Foxit reader as the default PDF reader we can set it very easily.
You can also read setting default browser in Windows
We can Set Foxit Reader as default PDF reader in 3 ways.
1.If you are opened Foxit reader for the first time you will be asked whether to set Foxit reader as default reader click Yes to make Foxit reader as Default PDF reader.
2.Open Foxit Reader ,From Help menu enable or select Set to Default PDF Reader.
3.Open My Computer select Tools>Folder options>select File Types and in registered file types
select PDF in them and in open with click Change ,select Foxit Reader.
Update: For versions> 6.0
Edit>Preferences>File Associations>Make Default PDF Viewer.