maybe this will fix it?

echoserver/echoserver.c

@@ -80,7 +80,7 @@ int main(int argc, char **argv)
             return -1;
         }
         // for loop that loops up to the max file descriptor.
-        for(int fileIter = 0; fileIter < maxFD; fileIter++)
+        for(int fileIter = 0; fileIter <= maxFD; fileIter++)
         {
             // check to see if the file descriptor is in the set of sockets using FD_ISSET()
             if(FD_ISSET(fileIter, &socketList))
@@ -141,7 +141,6 @@ int main(int argc, char **argv)
                 printf("\nDEBUG: Working or not?\n");
             }
         }
-
         // OLD CODE HERE
         // // grab the size of the listened clients
         // clientSize = sizeof(clientAddr);