Is corporate instant messaging free or charged?

? Enterprise instant messaging is free-what's the difference between the free version and the paid version of enterprise instant messaging? Time: 2020- 1 1-25. The free version needs external network support, but it needs to be able to access the Internet. The server is on their side, so it's better to check the chat records and pass the good news. Relatively free, more suitable for small and medium-sized enterprises. No IT personnel specialist, no server deployment and post-maintenance problems.