Random Innvocation Errors

Is there any reason why Samba would give me invocation errors at random. For instance:

-Invocation error when applying a discount on the settlement screen. Restarting the application it worked the second time.
-Invocation error when adding an order and hitting close. Again it worked when I reopened the pos.
-Invocation error when adding an item to a ticket. Against it worked when I reopened the pos.

We had our soft opening last night and this was a problem in the beginning, but it started to slow down later in the day. We have 4 pos’s and most were in use all at the same time. I have a few errors saved and I can post them later. I just don’t understand why it works after the program restarts.

J

Might relate with network connectivity. More info can be found in full error reports.