To set preferences for Security Server settings or other settings, choose File > Options > Security.
Configure Server Settings
Click More to configure Directory Servers or Time Stamp Servers. Choose the server type in the left panel.
Security Settings
Click Import or Export to load or save your security settings to a proprietary file type; you can choose any or all of three categories to import or export:
This import and export was previously done from the Security ribbon.
You can also load security settings from a server by providing its URL.
Select how settings files are to be verified by signatures. Choose Allow Any Certificate or choose any signature scheme you have established. Browse to locate the desired scheme.
Time checking interval
If you specified a particular scheme, choose a frequency for having it checked and settings updated if they have changed. The scheme file must remain at the URL provided.
See also: About Securing PDF, Sign/Certify panel and Security Properties.