Serial number missing on an item line, Zentriq

Business Central raises this when the item on the line is tracked by serial number and you have not told it which numbers are being posted. The quantity on the document line and the quantity assigned in Item Tracking Lines must match exactly. Open Item Tracking Lines on that line and assign a serial number for every unit before you post.

Why Business Central asks for a serial number

Any item whose Item Tracking Code requires specific serial number tracking for the direction you are posting has to be identified unit by unit. The serial number is what makes a single piece traceable from receipt to sale, so the posting routine refuses any quantity it cannot identify. Because one serial number covers one unit, ten pieces on a line need ten numbers, and the smallest gap between the line quantity and the assigned quantity stops the posting. When the routine knows which line failed, it adds the reference, for example: You must assign a serial number for item 1000. Line No. = '10000'.

The line carries a quantity of ten but only part of it, or none of it, has serial numbers in Item Tracking Lines.
The quantity on the line was changed after tracking was assigned, so the existing serial numbers no longer cover the full quantity.
A transfer order had tracking assigned on the shipment side only, or on the receipt side only, instead of both.

How to assign the serial numbers

Open the document that failed to post and select the line for item 1000.
Choose Line, then Related Information, then Item Tracking Lines to open the tracking page for that line.
Enter one row per unit with the Serial No. and Quantity (Base) of 1, or use the Assign Serial No. action so Business Central generates them from the number series on the item card.
On outbound documents such as sales orders, transfer shipments and negative adjustments, use Select Entries to pick numbers that are actually on hand instead of typing them.
Check the summary at the bottom of Item Tracking Lines: the undefined quantity must be zero, which means the assigned quantity equals the quantity being posted.
Close the page and post again. On a transfer order, confirm that the same serial numbers are present on the receipt side before posting the receipt.

How to avoid it next time

Assign item tracking when the line is created rather than at posting time, and re-open Item Tracking Lines whenever a quantity changes, because the assignment does not follow that change. On the Item Tracking Code card, review which of the serial number options you really need for inbound, outbound and warehouse movements: switching tracking on for directions the business does not actually control creates work at every posting. Filling the Serial Nos. field on the item card also lets the Assign Serial No. action complete the lines in one click for goods you number yourself.

Frequently asked questions

Can I post part of the quantity without serial numbers?

No. The assigned quantity has to equal the quantity being posted on that line. If you only want to post part of it, reduce the quantity to ship or to receive on the line and assign serial numbers for that smaller quantity only.

Why does the message sometimes name a line number?

The posting routine adds Line No. = '10000' when it can identify the failing line. Use it to go straight to the right line, because a document with many lines may be missing tracking on only one of them.

"You must assign a serial number for item 1000."