that is simple!
kantipur saptahik does not open in Kantipur font but rather in Kalimati font. Otherwise, your browser doesnot support unicode or control panel hasnt the appropriate nepali fonts. Probably you are not running uptodate version of operating system.
Kantipur saptahik is in pdf format. So you have to download it now. In the control panel section of your computer, click the folder FONT and install font from the file menu. Therein, choose the font called kalimati that you have downloaded. if you have other fonts such as HImal, Nepal, downloaded too etc in your computer install it too . Hope it will works.
To download Kalimati and the rest fonts, go to Nepalnews.com, click any one of the weekly newspaper, such as Janastha, Budhabar on the left column, and therin you will find the links to download font in fontdownload section in the left column of the webpage