base64out() wasn't closing the attached file (so it couldn't be deleted).

src/sbbs3/mime.c

@@ -133,6 +133,7 @@ BOOL base64out(SOCKET socket, char * pathfile)
     if(i!=-1)   /* already printed the last line */
         sockprintf(socket,line);
     sockprintf(socket,"");
+	fclose(fp);
 	return(TRUE);
 }