Exchange Error while preparing to send sharing message

[karldenton]

Hi,

 

We've got the error "Error while preparing to send sharing message" when users try to share their outlook calendar or tasks folder. However it does work for some users.

 

I'm presuming the older ones worked on an old version of exchange and its been upgraded.

 

I just started so don't 100% know what the setup is.

 

I've read about auto discovery but not sure what to check on.

 

Any help appreciated

 

Thanks