I recently bought 16 GB SD card to store music on my Samsung Galaxy S2. I transferred about 500 songs from my pc to this new SD card but when I open the default music player app on my Galaxy S2 I can see only 15-20 songs. Where are the rest of the songs? Same SD card works perfectly on my brothers Sony Xperia Z1. Can anyone please help me to figure out what is wrong with my Galaxy S2?
Check if those songs are in a format which is supported by the music player you are using. If they are in Mp3, this is obvious. If not, check your app's compatibility.
Check if the SD card is recognized by your phone at all: open a file manager and see if you see it and can navigate through it
Check if your media player is looking in the SD card: go in your player's settings and check your library options. Note that music players offer filters (to avoid ringtones and such be included in your library): they go from name, to format, to length, to folder. Check all those filters. Then do a library rescan
.nomediafiles inside the main folder of your SD card or of your music archive: if such a file is included, your media player is told to skip that folder in order to avoid including ringtones and such, again
Check if your songs are properly tagged. Music players will organized your library with tags (informations about Artist, Album, Genre, Year, Track Number and Title) rather than location and filename.