How to reset diagnostics for particular block?

Hi, In my simulink simulation I am using a "transport delay" and I think I have disabled some diagnostics regarding this block. But I can not find them. I am trying to find out the buffer size I need to set for one of my simulations but I never get the warning that is mentioned in the help files when the initial buffer size is set to low (even when setting the initial buffer extremely low):

Initial buffer size

Define the initial memory allocation for the number of input points to store

Settings

Default: 1024

• If the number of input points exceeds the initial buffer size, the block allocates additional memory.
• After simulation ends, a message shows the total buffer size needed.

Does anyone know how I can rectify this?

[Kaustubha Govind]

What is the Maximum Delay setting and what do you provide for the second (transportation delay) input? Perhaps even the extremely low buffer size that you specify is sufficient for your signal if the delay is small enough?