Whenever I try and install a custom sim - either from the Exchange or from ModTheSims - the sim will grey out in the Downloads section in the launcher and will appear in the Installed Content section, however when I start the game the sim does not appear in the Premade Sim bin, and when I exit the game an check the launcher, they disappear from the Installed Content section and will no longer be greyed out in the Downloads section. I also have this problem with two bits of custom hair, but oddly enough I've managed to install three custom pets with no problems.

I have all of the expansion packs/stuff packs, and my game is fully updated. I've had this problem for a long time, since I started trying to install sims (middle to end of last year).

• Sims 3 - Launcher and/or EADM Issues
  If you encounter issues while downloading Store/Exchange items or when trying to patch or Launcher won't even start, please try the suggestions on these FAQ articles:
  
  • Game Help:Launcher Issues^wiki
  • Game Help:EADM Issues^wiki
  
  

This is a very, very common issue - just bad EA coding. The tips above may help. :) If not, you'll have to stick to .package/.sim files (which all the sims on MTS are available as, btw).

I've tried this and nothing changes

However, someone else directed me to "Delphy's Sims 3 Pack Multi-Extracter" and that's solved my problem perfectly. I think I read somewhere that converting sims with this corrupted the files and caused all sorts of game problems, like lag or something, but so far my game seems just as laggy and generally s**t as usual

Thanks for your help though :D