Can only copy certain songs and albums to my 4s using itunes - HELP

[cloud106]

Have never had a problem using iTunes or my iPhone before until today and i'm pulling my hair out with it now so thought id throw the question out on here. Basically this morning I thought id remove all the music on my iPhone because I was getting a bit bored of it and then re apply music using my iTunes library. So I deleted all my albums on the phone itself and connected it to my computer. I have my configuration set to manual so I can just drag and drop all the songs I want in my iPhone instead of it syncing my whole library to my phone whenever its connected, so anyway I started looking through my music and dragged an album I wanted into my iPhone and nothing happened, no error codes no failure messages, just nothing. Then I tried to right click the album and add to the my iPhone playlist and again nothing. I can always tell when everything is going ok because I look for the syncing symbol on my iPhone when I do this but just nothing was happening. So I start trying other albums and some start syncing and some just don't do anything which is really starting to annoy me. Its not just CD's that wont sync some actual purchased songs wont either and I cant understand why?? I tried restarting iTunes, checking for updates, restarting the PC, restarting my phone but its not making any difference. All the music will play ok on the computer so the files cant be corrupt. Its as if it will only copy over what it can be bothered too. Can anyone advise on this issue please? would be much appreciated

 

[Gregoris]

is it all in the same format? also check the size of all of the songs, does your ios device have enough to load it all on there?