It sounds like you think you have wampserver2.2 and wampserver2.4 installed but you dont as the Apache and MySQL services will be registered as running from the last version you installed. Which will be 2.4 I assume?
Try this out for size:
!!! Make copies of everything you dont want to loose just in case !!!!
Uninstall Wampserver.
Rename \wamp folder, which will still exist as the uninstall does not remove files it did not create or files that have changed since the install, so you keep any site code and databases you may want later.
Install WampServer 2.4
Check it works as installed.
Read this post and make the changes it suggests
Wampserver 2.4 What to do after Installing [
forum.wampserver.com]
Now copy any versions of Apache and MySQL you want to keep from the old wamp folder to the new one.
So thats copy \oldwamp\bin\apache\apachex.y.z\* to \wamp\bin\apache\apachex.y.z\*
and copy \oldwamp\bin\mysql\mysqlx.y.z\* to \wamp\bin\mysql\mysqlx.y.z\*
Restart WAMPServer so it recognises all the changes and you should be able to switch between versions of Apache at will.
Now there is a GOTCHA I am afraid. Recently The Apache and PHP communities have been changing the versions of the MSVC++ compiler they use to build Apache and PHP. So the switching process has become a little more difficult. You have to run an Apache and PHP together that are compiled with the same version of the compiler. If you get a mismatch you will get the sort of errors you say you are getting.
This may mean you need to install a version of Apache and or PHP that you dont actually want to use so that you can step back via versions that work together.
---------------------------------------------------------------------------------------------
(Windows 10 Pro 64bit) (Wampserver 3.3.4 64bit) Aestan Tray Menu 3.2.5.4
<Apache versions MULTIPE> <PHP versions MULTIPLE> <MySQL Versions MULTIPLE>
<MariaDB versions MULTIPLE> <phpMyAdmin versions MULTIPLE> <MySQL Workbench 8.0.23>Read The Manuals Apache --
MySQL --
PHP --
phpMyAdminGet your Apache/MySQL/mariaDB/PHP ADDONs here from the
WAMPServer alternate Repo-X-X-X-
Backup your databases regularly Here is How dont regret it later! Yes even when developing -X-X-X-