Problem chat

I have the eM Client on a Windows Server 2012 R2 server all users work emails and chats, plus I have cases that when they try to open the chat closes the eM Client.

Hello Thiago,

do you get any error message regarding eM Client crash? Are you referring to built-in chat feature in eM Client?
Please also clarify what version of eM Client is affected.

Yes Internal Chat, Version 7.0.27943.0

Do you get any error message regarding eM Client crash?