Hi, we are trying to migrate some users from Exchange 2003 to ZCS and we are using the Exchange Migration Wizard. We get some warnings about messages that is skipped because of sizes. The manual tells me the following:

Note: You can modify the following registry key to change the default limit:
HKCU\Software\Zimbra\MaxAttachSizeMB. The registry key should be
specified in megabytes (MB).

I don't have this particular registry key in HKCU\Software\Zimbra, can I create it? (I have the zimbra folder, but not the particular registry key).