Put simply, the purpose of rehashing is to clear out old saved parameters to load new ones. The system, by default, collects some parameters in a cache. This is all well and good, until you need to load new parameters! This is where rehashing comes in.
There are two ways to rehash your system: using the chatroom's command features, or manually removing the old files. When possible, use the chatroom's command, as it will save time and prevent you from making a mistake.
To use the software to perform the rehash quickly, enter the chatroom and ensure that you have Admin. Once authorized, simply type /rehash into the text line. If you have the proper credentials, the system will indicate you have successfully rehashed the chat.
It's important to note that some parameters are also session specific, so you may need to close your browser and wait a couple of minutes before you will be able to see the changes.
Occasionally automated rehashing is not possible, because the chatroom is not available or admin cannot be obtained. In this case, you will want to perform a manual rehash.