net send /Domain:KRUTAJAFIRMA "Привет от админа :)"

net help send

C:\WINDOWS\system32>net help send | more
The syntax of this command is:


NET SEND
{name | * | /DOMAIN[:name] | /USERS} message


Sends messages to other users, computers, or messaging names
on the network. The Messenger service must be running to receive messages.

You can send a message only to a name that is active on the network.
If the message is sent to a username, that user must be logged on
and running the Messenger service to receive the message.

name                   Is the username, computername, or messaging name
                       to send the message to. If the name is a
                       computername that contains blank characters,
                       enclose the alias in quotation marks (" ").
*                      Sends the message to all the names in your group.
/DOMAIN[:name]         Sends the message to all the names in the
                       workstation domain. If name is specified, the
                       message is sent to all the names in the specified
                       domain or workgroup.
/USERS                 Sends the message to all users connected to
                       the server.
message                Is text to be sent as a message.

NET HELP command | MORE displays Help one screen at a time.

sc config messenger start= auto
net start messenger

net start eventlog 

sc config eventlog start= auto
net start eventlog