When you use the Canadian/UK version of All Orders you may get the above error when recording a bill to QuickBooks. Try unchecking 'record adjustment as bill' in the QuickBooks Synchronization Preferences. This preference is located in All Orders. Go to the menu Company, Preferences, QuickBooks Synchronization. Below on the Inventory tab, uncheck Post Inventory Adjustments as Bills in QB.
If changing the preferences does not work, try a way around this by rounding the adjustment. Do this by changing thru GENERAL PREFERENCES the number of digits to only TWO decimal places on the quantity or no decimal place at all. You can reverse this change after the adjustment posts.
Ultimately as a way around, you can just do an NC Only Adjustment and then enter a corresponding similar adjustment in QB. Do this if concerned about adjusting serial numbers or bin quantities, however if the concern is only the the total quantity, you may just want to enter the adjustment in QB and then sync.