Hi,
You already posted a message about a fatal error message 2 days ago which was linked to an old version of an extension provided by JEvents:
www.hikashop.com/forum/install-update/90...verything-broke.html
I answered you there that you need to update it.
Are you talking about the same error ?
Did you contact JEvents about it ?
If it's the same error message, I can't tell you more than what I tell you there.
If it's another error message, please provide it. Otherwise, I don't know what is the problem and thus I can't tell you what to do, especially since it's probably not an error in HikaShop but in something else integrating with HikaShop in some way.