This can happen with JumpStart or Power Ops when creating matrix items using the AutoGen option for AC (auto-categorize) or AS (auto-supplier code prefix).
Method A Duplication:
If the user creates a matrix using the AC or AS option, the Item Lookup Code generated for matrix uses the associated prefix then append X digits to the matrix components depending on the setting.
Right after creating the matrix if the user deletes the matrix master and then recreates a matrix using the same options, the matrix master will get the same ILC as the one you just deleted and the components can get the duplicate codes because the components from the previous matrix are still in the database.
This should be a very rare occurrence though. All other situations are handled by our code. We check for each component to make sure the ILC is not already in the database.
Rename the ILCs manually and avoid deleting a matrix entry and immediately adding a new matrix with same base code.
Method B Duplication:
Another way to generate duplicate codes is if you set sequential digits to 3 digits and run past 999 entries. If you have reached 999 in the series, you will need to run AutoGen and increase the sequential digits from 3 to 4 or 5 digits. 4 digits = 9999 possible entries. 5 digits = 99999 possible entries in any series.
If you are using the Custom ILC option in Power Ops, verify the sequential number limit has not been reached. If so, increase the value.
Adjust AutoGen to include a higher range of sequential numbers.
If you are using Custom ILC in Power Ops, edit the format to increase sequential number size or design a new format for generating Item Lookup Codes.
Method C Duplication:
Your existing Item Lookup Codes have trailing spaces that need to be removed.
To remove the trailing spaces, download the attached query below. Run Store Operations or HeadQuarters Administrator and select File, Connect. Enter your database connection setting and click OK. Select File, Open and locate the query. Press F5 to run it.