So SARP's updated to 0.3.dl which is now needed to play the server.
First, close out of the samp client.
head to your GTA folder, and look for SAMP uninstall. Double click it and uninstall it.
Go here: http://forum.sa-mp.com/showthread.php?t=648633 and download the client installer.
Open it and select your GTA folder, and install the new version.
Keep in mind some modifications do not work on this version so if you're still having trouble, try on a clean install of the game then import your mods one at a time to see if they work or not. Skin, weapon, car, etc mods should be fine.