[KWo]

What the version of AMX do You have? All AMX plugins need to be called from the file plugins.ini (but this one existing in AMX\config directory; not this one in metamod directory).
The call for AMX plugins is for example this:

----pllugins.ini file----

; AMX Mod plugins

; To disable any plugin, add a semi-colon ';' to the beginning of its line

; You can disable the Just-In-Time (JIT) compiler with the 'nojit' keyword:
; pluginname.amx nojit
; (read the docs for more details)

; Note: you don't need to declare csstats.amx here (CSStats will load it)


language.amx ; language management

adminlog.amx

admin.amx ; admin base (required for any admin-related)
;admin_mysql.amx ; admin base - MySQL version (comment admin.amx)
admincmd.amx ; basic admin console commands
adminhelp.amx ; help command for admin console commands
;adminslots.amx ; slot reservation
menufront.amx ; front-end for admin menus
cmdmenu.amx ; command menu (speech, settings)

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your_custom_plugin1.amx
your_custom_plugin2.amx
your_custom_plugin3.amx