The profiles of email archive are XML files, in general, people can open all profiles with text editor (such as notepad++), and mass update the configuration of profiles.

Specifically for updating client id and client secret

• stop the email archive service first
• backup all original profiles in C:\ProgramData\Laserfiche\EmailArchiveService\Profiles to C:\ProgramData\Laserfiche\EmailArchiveService\Backups
• open email archive config to edit clientid and clientsecret of a profile, profile A for example, and save
• open profile A in C:\ProgramData\Laserfiche\EmailArchiveService\Backups with text editor to get the old value of ClientId and ClientSecret in <ImapServerSettings>. 
• open profile A in C:\ProgramData\Laserfiche\EmailArchiveService\Profiles with text editor to get the new value of ClientId and ClientSecret in <ImapServerSettings>. 
• open all profiles in C:\ProgramData\Laserfiche\EmailArchiveService\Profiles, replace all old values with new values in all XML files, and save
• restart the service