diff --git a/deluge/core/rpcserver.py b/deluge/core/rpcserver.py
index a4e8a7e62..6b77881e2 100644
--- a/deluge/core/rpcserver.py
+++ b/deluge/core/rpcserver.py
@@ -169,8 +169,10 @@ class DelugeRPCProtocol(Protocol):
 
         # We need to remove this session from various dicts
         del self.factory.authorized_sessions[self.transport.sessionno]
-        del self.factory.session_protocols[self.transport.sessionno]
-        del self.factory.interested_events[self.transport.sessionno]
+        if self.transport.sessionno in self.factory.session_protocols:
+            del self.factory.session_protocols[self.transport.sessionno]
+        if self.transport.sessionno in self.factory.interested_events:
+            del self.factory.interested_events[self.transport.sessionno]
 
         log.info("Deluge client disconnected: %s", reason.value)