RE: Upgrade for NAV 2013 R2 to NAV 2018 has taking more than 4days because of product groups?
It make sense and the reason is data.
Follow these steps -
1. Open Item category table and check any record with Code = '' (Delete that).
2. Run Product Group Table and check for any record with Item Category code = '' (Delete that).
3. Check Product Group table has unique record w.r.t Code field. If two product group code records have same value for Code then rename and keep it unique.
What these are required -
1. During upgrade data from these two tables will get consolidated in one table.
2. Item Category table data is set to Parent Record and Product Group data is set as child record.
3. Each Child Record is set to Parent code to show data to user.
If any data exist with three cases discussed above upgrade logic goes into a endless loop.
Let me know if any questions.