Why I cant open dowmloaded files ?

[Android Central Question]

What shoul i do ciz i cant open the downloaded files.....? F i open it in the microsoft ofice like word i can but i cant in my files...i cant in my files i cant transfer it also.?

 

[ManiacJoe]

Where are the files located? Internal storage or SD card? Which folder?
What kind of files are they? (what are the file extensions?)

Do you have the necessary apps to read such files?