How to migrate from Mark Jaquith's Subscribe to Comments plugin to Gurken's new version?

Question

Mark Jaquith's Subscribe to Comments plugin has been a staple of my WordPress site since shortly after I launched it. However, it's not really maintained any more (last updated end of 2007) and it lacks some options (email verification, etc.).

infogurke extended Mark's plugin and released a different version with enhancements:

• All of the original Subscribe to Comments
• Registration with Double-Opt-In
• Multi-Language (English and German included)
• You can define an own css file for the manager interface
• Fixed many bugs that are still in the original plugin

Is it possible to migrate to infogurke's version and maintain the subscriptions in the database?

(Found the new plugin via this question.)

Answer 1

Yes, it's possible (and quite easy) to migrate from Mark Jaquith's Subscribe to Comments plugin to Gurken Subscribe to Comments plugin.

The steps:

1. Install Gurken Subscribe to Comments (using either FTP or WordPress's plugin manager)
2. Don't activate Gurken StC yet. First deactivate Mark Jaquith's version.
   • Activating the new plugin too soon will fail because both plugins define functions with the same names.
3. Activate Gurken StC.
4. Go in via FTP and delete the /wp-content/plugins/subscribe-to-comments/ folder.
   • Don't use WordPress to delete Mark's version! It might erase your subscription data from the database!

(Question and answer inspired by this WordPress Support thread.)