Procedure:

1. Log in to the SMS from a client.
2. Click the Devices tab, select the Device with blocked streams, and then expand the navigation tree.
3. Select Events and then select the Blocked Streams tab.
4. To flush a subset of blocked streams, you can narrow down your selection by configuring the search by setting the Protocol, Source or Destination Address, and Port.
5. Then select one or more of the following:
   • One stream
   • Multiple streams
6. Select Flush in the lower right to perform the flush.
7. To Flush All blocked streams, click the Flush All button on the lower right.
8. Click Refresh to view the flush results.

Reference: SMS User Guide