Title: 4.2.1 error
Last modified: August 24, 2016

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# 4.2.1 error

 *  Resolved [drpeisner](https://wordpress.org/support/users/drpeisner/)
 * (@drpeisner)
 * [10 years, 11 months ago](https://wordpress.org/support/topic/421-error/)
 * Can you please tell me how to activate the plug in in 4.2.1? I get fatal error.
   Thank you.
 * [https://wordpress.org/plugins/wp-testing/](https://wordpress.org/plugins/wp-testing/)

Viewing 6 replies - 1 through 6 (of 6 total)

 *  Plugin Contributor [ustimenko](https://wordpress.org/support/users/ustimenko/)
 * (@ustimenko)
 * [10 years, 11 months ago](https://wordpress.org/support/topic/421-error/#post-6080317)
 * Can you show the error? I tested it on 4.2 and this will be in next release, 
   but currently it most possibly not related with 4.2.1.
 *  Thread Starter [drpeisner](https://wordpress.org/support/users/drpeisner/)
 * (@drpeisner)
 * [10 years, 11 months ago](https://wordpress.org/support/topic/421-error/#post-6080369)
 * Plugin could not be activated because it triggered a fatal error.
 * This is the error message when I try to activate. Thank you for your help. I 
   am very excited to test this and if it works for my needs I will pay for some
   customization if you are willing.
 *  Plugin Contributor [ustimenko](https://wordpress.org/support/users/ustimenko/)
 * (@ustimenko)
 * [10 years, 11 months ago](https://wordpress.org/support/topic/421-error/#post-6080387)
 * Currently I activated it on 4.2.1 — it’s ok.
 * Most possibly it’s related with another plugins or permissions.
 * Can you try to disable other plugins and activate?
 * Another possible reason is some theme, that do too much.
 * If you will not find th reason — you can create temp admin for me and I’ll try
   to figure out the reason. Pls dont’ give me your admin details — just create 
   new in users.
 * My email is [a@ustimen.co](https://wordpress.org/support/topic/421-error/a@ustimen.co?output_format=md)
 *  Plugin Contributor [ustimenko](https://wordpress.org/support/users/ustimenko/)
 * (@ustimenko)
 * [10 years, 11 months ago](https://wordpress.org/support/topic/421-error/#post-6080444)
 * > Good news everyone!
 * I found an error:
 *     ```
       Warning: mysqli::mysqli(): The server requested authentication method unknown to the client [mysql_old_password]
       in wp-content/plugins/wp-testing/vendor/ruckusing/
       ruckusing-migrations/lib/Ruckusing/Adapter/MySQL/Base.php on line 1137
   
       Could not connect to the DB, check host / user / password
       ```
   
 * I’ll try to repeat it somehow locally and will release a hotfix ASAP.
 *  Plugin Contributor [ustimenko](https://wordpress.org/support/users/ustimenko/)
 * (@ustimenko)
 * [10 years, 11 months ago](https://wordpress.org/support/topic/421-error/#post-6080446)
 * In the meantime try to solve it somehow from your side:
 * [https://dev.mysql.com/doc/refman/5.5/en/old-client.html](https://dev.mysql.com/doc/refman/5.5/en/old-client.html)
 * Contact your hosting or try to play with control panel.
 *  Plugin Contributor [ustimenko](https://wordpress.org/support/users/ustimenko/)
 * (@ustimenko)
 * [10 years, 11 months ago](https://wordpress.org/support/topic/421-error/#post-6080537)
 * Hi, I found a reason and how to fix it.
 * **How To Fix**
 * Create another mysql user with same rights and password but another login. Then
   use this user in your wp-config.php
 * For example you have login/password foo/bar there — then just create mysql user
   foo2 with same rights. It’s for possibility to instantly update mysql user login
   to new, check that all is ok and in case of problems instantly switch back to
   old.
 * **Technical Details**
 * In your concrete case your mysql user stores password in database in old less
   secure format. May be it’s an issue of your hoster. In PHP there are 3 ways to
   connect to Mysql: deprecated and two modern. Also they are all can use one of
   two possible low-level drivers: old-one that understands unsecure passwords and
   new-one that not.
 * In your case we have these combinations:
    – old way to connect with possibility
   of insecure passwords – modern way to connect without insecure passwords
 * WordPress by default uses old way to connect — that’s why it works. But plugin
   in two different places uses only new way — that’s why it’s broken now in this
   combination.
 * **Fix Policy**
 * I thought I will release some hotfix, but now see — I will not do it ASAP as 
   situation is rare, we have workaround and now it will costs too much.
 * PS: Now you can disable those tmp admin 2nd time. When all becomes working, pls
   ping back here.

Viewing 6 replies - 1 through 6 (of 6 total)

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## Tags

 * [wp-testing-bug](https://wordpress.org/support/topic-tag/wp-testing-bug/)
 * [wp-testing-support](https://wordpress.org/support/topic-tag/wp-testing-support/)

 * 6 replies
 * 2 participants
 * Last reply from: [ustimenko](https://wordpress.org/support/users/ustimenko/)
 * Last activity: [10 years, 11 months ago](https://wordpress.org/support/topic/421-error/#post-6080537)
 * Status: resolved