[Fastmancz]

Hi,

I use timer for Welcome message.

PHP Code:

public OnPluginStart()
{
CreateTimer(5.0, Welcome);
}

public Action:Welcome(Handle:timer, any:client)
{
  new String:name[32];
  GetClientName(client, name, 32);
  PrintToChat(client, "Welcome on server %s", name);
} 


Problem:
[SM] Native "PrintToChat" reported: Client index 0 is invalid.

Where is problem? I use Handle:timer on other plugin and problem is same.

[Impact123]

Take a look at the definition of the CreateTimer function.
Its third parameter is passed to the callback and it defaults to INVALID_HANDLE which is defines as 0.
Since you didn't pass a third parameter to CreateTimer, your callback will receive the default value of 0.
With that out the way, you'll probably understand that you code cannot work like that because there is no client index you pass.
Please note that you should not use client id's for timers, use a client serial or user id instead. The wiki has an example (the second one) of what you want to do.

[RedSword]

You also might want to either launch the timer OnClientConnected and pass the client user id / client serial id (as said by Impact123) and revert it back to a client Id in the Timer callback function, or simply loop from 1 to MaxClients if you really want it to start OnPluginStart (depending on what you really want to do).