Hi,
I'm afraid this only looks easy, but isn't. I'll try to explain.
The physical inventory posts two kinds of entries:
1. physical inventory entries for the fact that the item has been counted, and with what quantity (and where).
2. item ledger entries for any deviations in stock (positive/negative adjustment).
To achieve this a special journal has to be filled, which - despite its appearance - can only be filled with the batch "calculate inventory". This batch calculates the inventory at date (no date delimiter possible or intended) by item, and optionally by location, bin, variant code. These are the expected physical inventory quantities. The counted quantities need to be entered into the phys. inventory journal. The NAV logic then calculates the deviation to be posted.
So, these are several problems:
1. You need the physical inventory at the date of stock-tacking. The database has certainly evolved from this date, and NAV has currently no (standard) way of calculating the stock at a certain date by location and by bin. This needs a customization to fill the phys. inventory journal corectly.
2. Importing your excel file would either need to match existing journal lines, or the import needs to duplicate the logic which creates the phys. inventory journal lines, also with respect to problem 1.
I would suggest that you talk to your NAV partner for assistance in this matter, or an in-house consultant who has experience in NAV inventory. But as I said, this is no easy task, nothing for trainees / inexperienced coders.
with best regards
Jens