Typically  the error message you are receiving is due to Quick Books not allowing FieldOne to communicate with Quick Books. In order to resolve this issue, you need to log into QB as Administrator and allow FieldOne as an integrated software. This can be accomplished by going to Edit > Preferences > Integrated Applications and adding FieldOne as an excepted program to integrate with QB.

The 808 error code usually indicates that FieldOne tried to export a
transaction and link it to a non-exiting customer/employee/vendor/item
etc.  in QB. One of the common reasons for that might be if the name
of that customer/employee/vendor etc. in QB doesn’t match the QB Name of that related customer/employee/vendor etc. in FieldOne. The error code will
typically indicate which item/customer/employee/vendor… does not match. Check both QB and FieldOne to make sure they are matched exactly.

The 805 error usually indicates that FieldOne tried to add an customer, vendor or item etc to Quick Books while there is another record in QB with the same name. (Note, that QB has a limitation that Customer, Employees, Vendors, Other Names, etc all have to be unique, which means you cannot have a customer and Vendor in QB with the same name). To get around this limitation QB suggests renaming one of them, for example by adding a dot to the name.

In FieldOne, we use Branches. Your Branches can be set up by selecting the pull down arrow next to the System tab and choosing Company Branches. Within each Branch, there is a field called “QB Class Name”, which you can use to link the Branch to the appropriate Class in QB.  When exporting invoices the system will link the exported Invoice in QB to the Class associated with the Branch used on the Invoice in FieldOne. By default the Branch set on the
Invoice is taken from the Branch set on the Work Order. The Branch set on the
Work Order is set by default to one of the following:  if Branch is set on the
Job Site then it uses that Branch otherwise it will use the Branch set on the
Employee info of the logged in user

The FieldOne application running QB integration and the QB application must be running on the same computer and the comapny file to which they are exporting must be open.  This can be done on any client computer and it does not have to be the server.