diff --git a/telethon/errors/__init__.py b/telethon/errors/__init__.py
index ca050de9..2704fed7 100644
--- a/telethon/errors/__init__.py
+++ b/telethon/errors/__init__.py
@@ -66,23 +66,5 @@ def rpc_message_to_error(rpc_error, report_method=None):
             capture = int(m.group(1)) if m.groups() else None
             return cls(capture=capture)
 
-    if rpc_error.error_code == 400:
-        return BadRequestError(rpc_error.error_message)
-
-    if rpc_error.error_code == 401:
-        return UnauthorizedError(rpc_error.error_message)
-
-    if rpc_error.error_code == 403:
-        return ForbiddenError(rpc_error.error_message)
-
-    if rpc_error.error_code == 404:
-        return NotFoundError(rpc_error.error_message)
-
-    if rpc_error.error_code == 406:
-        return AuthKeyError(rpc_error.error_message)
-
-    if rpc_error.error_code == 500:
-        return ServerError(rpc_error.error_message)
-
-    return RPCError('{} (code {})'.format(
-        rpc_error.error_message, rpc_error.error_code))
+    cls = base_errors.get(rpc_error.error_code, RPCError)
+    return cls(rpc_error.error_message)
diff --git a/telethon/errors/rpc_base_errors.py b/telethon/errors/rpc_base_errors.py
index 3ec6cc7e..061740d8 100644
--- a/telethon/errors/rpc_base_errors.py
+++ b/telethon/errors/rpc_base_errors.py
@@ -97,6 +97,19 @@ class ServerError(RPCError):
         self.message = message
 
 
+class BotTimeout(RPCError):
+    """
+    Clicking the inline buttons of bots that never (or take to long to)
+    call ``answerCallbackQuery`` will result in this "special" RPCError.
+    """
+    code = -503
+    message = 'Timeout'
+
+    def __init__(self, message):
+        super().__init__(message)
+        self.message = message
+
+
 class BadMessageError(Exception):
     """Occurs when handling a bad_message_notification."""
     ErrorMessages = {
@@ -142,3 +155,9 @@ class BadMessageError(Exception):
             'Unknown error code (this should not happen): {}.'.format(code)))
 
         self.code = code
+
+
+base_errors = {x.code: x for x in (
+    InvalidDCError, BadRequestError, UnauthorizedError, ForbiddenError,
+    NotFoundError, AuthKeyError, FloodError, ServerError, BotTimeout
+)}
diff --git a/telethon/tl/custom/message.py b/telethon/tl/custom/message.py
index 2124249f..50af0bd4 100644
--- a/telethon/tl/custom/message.py
+++ b/telethon/tl/custom/message.py
@@ -556,7 +556,7 @@ class Message:
         if sum(int(x is not None) for x in (i, text, filter)) >= 2:
             raise ValueError('You can only set either of i, text or filter')
 
-        if not self.buttons:
+        if not await self.buttons:
             return  # Accessing the property sets self._buttons[_flat]
 
         if text is not None:
diff --git a/telethon/tl/custom/messagebutton.py b/telethon/tl/custom/messagebutton.py
index cf970c39..80525218 100644
--- a/telethon/tl/custom/messagebutton.py
+++ b/telethon/tl/custom/messagebutton.py
@@ -1,4 +1,5 @@
 from .. import types, functions
+from ...errors import BotTimeout
 import webbrowser
 
 
@@ -65,11 +66,13 @@ class MessageButton:
             req = functions.messages.GetBotCallbackAnswerRequest(
                 peer=self._chat, msg_id=self._msg_id, data=self.button.data
             )
-            return await self._client(req, retries=1)
+            try:
+                return await self._client(req)
+            except BotTimeout:
+                return None
         elif isinstance(self.button, types.KeyboardButtonSwitchInline):
-            req = functions.messages.StartBotRequest(
+            return await self._client(functions.messages.StartBotRequest(
                 bot=self._from, peer=self._chat, start_param=self.button.query
-            )
-            return await self._client(req, retries=1)
+            ))
         elif isinstance(self.button, types.KeyboardButtonUrl):
             return webbrowser.open(self.button.url)