If you are receiving a file with an extension of 3GP or 3GPP then it is a multimedia file name 3gpp Multimedia File. These kinds of files are mostly audio or video files. Other kind of files like photos, and many more programs also uses this 3gpp file extension. Before you going to open these kinds of files of extension 3GPP assume that whether they are files to be viewed only or they are in read/write format.
In addition to the problem described above, i.e. the lack of the appropriate application to support the .3GP file, there may be several reasons that cause problems with opening and operation of the data format:
A quite common problem is the lack of application in the appropriate version. Even if you have an application, with the help of which you should open the .3GP file, you may have a problem with it because of its version. Perhaps in previous versions the application has not yet supported the .3GP file, so download the update and check again.
If you have already installed the appropriate application, and it is the correct version, the file may not open correctly, because the operating system does not have information that this program supports the file. So you need to "show" which program the computer should use. To do this:
It also happens that the file you want to open is corrupt and therefore there is no such possibility. In this situation, you should find its different version, or ask a person from whom you got, to send it again. You can also try to find more informations about this file extension here.