Calendar system and instant messenger centrally located

[ColdAsIce]

Hi everyone,

My work place are looking for a calendar system and ideally an instant messenger that would be run centrallly from a server or a dedicated pc within the work place.

The calendar needs to be seen by all staff and be up-dated in real time.

Does anyone have any recommendations? Staff size is probably around 250.

 

[Burnsy2023]

Microsoft Exchange with Lync Server. 250 clients is reasonably sized.

 

[Sunbed]

Google Apps for Business?

Obv not located locally though.