This error means that file was not found. Either path is wrong or file is not present where you want it to be. Try to access it by entering source address in your browser to check if it really is there. Browse the directories on server to ensure the path is correct. You may even copy and paste the relative path to be certain it is alright.
Use <img src="images/OIP.jpg"> not as <img src="images/OIP.jpg"/> Remove the / in the path.