I was getting timeout error while executing a stored procedure from the web application. But this stored procedure is executing within a second while running from SQL management studio. This issue can happen when database's statistics and/query plan cache are incorrect. This can be resolved by updating statistics by executing exec sp_updatestats Error: Timeout expired. The timeout period elapsed prior to completion of the operation or the server is not responding. Solution: exec sp_updatestats If issue didn't resolve even after executing above this, you may need to optimize the query.
Service not available, closing transmission channel. The server response was: 4.4.2 Message submission rate for this client has exceeded the configured limit
Error: Service not available, closing transmission channel. The server response was: 4.4.2 Message submission rate for this client has exceeded the configured limit Solution: Increase the default message rate limit (it was 5 on my case) Set-ReceiveConnector -Identity " EXCHANGE_NAME \Client Proxy EX01" - MessageRateLimit 200