Sage Knowledgebase article link:

support.na.sage.com/.../viewdocument.do

Description
How to merge vendors using the Delete and Change Vendors utility

Disclaimer
Backup Warning
Use caution when working with the below product functionality. Always create a backup of your data before proceeding with advanced solutions. If necessary, seek the assistance of a qualified Sage business partner, network administrator, or Sage customer support analyst.

Resolution
To change or merge vendor numbers

Open Accounts Payable Utilities menu > Delete and Change Vendors.
Select the Change tab (the default is to the Delete tab)
Enter the starting vendor number and ending vendor number to select a range of vendor numbers to change. You can also enter the wildcard character (*) to select all matching vendor numbers. For more information, see Delete and Change Vendors – Fields.
In the New Vendor No. field, perform one of the following:
Enter the new vendor number for the selected vendors to be Merged into.
Enter an existing vendor number to merge vendor information with the selected vendor.
Click the Resolve Wildcards button to list each vendor number, either in the selected range or selected by wildcards, on a separate line.
Click the Print button.
In the Delete and Change Vendors Listing window, click Print.
You must print and clear the listing before you can complete another change or merge.
Perform one of the following:
Click Proceed to begin vendor change or merge.
Click Delayed to begin vendor change or merge at a later time. In the Delayed Execution window, in the Will Begin at Approximately field, type the time to begin and click OK. For more information, see Delayed Execution - Fields.
The vendor number is changed or merged.

Note If the Inventory Management and/or Purchase Order module is integrated with Accounts Payable, rebuild the Purchase Order and Inventory Management sort files along with the sort files for any other affected modules after vendor numbers are deleted or changed. For more information, see Rebuild Sort Files.

Bump! I'm being hampered by something interesting in my effort to merge duplicate vendors. While I'm not surprised to see this:

... what does surprise me is that clicking More Info displayed a massive list of users and files they've "locked". Even more, many of these users are no longer employed, some for quite some time.

For what it's worth, this list seems to have nothing to do with the information displayed in the Master Console.

What, exactly, are these locked files? What locks them? (Tasks that a user last accessed, perhaps, before they left the company?) Can they be unlocked? If so, how? (Can an end-user like me unlock them? Or does this need to be done by our local Sage support staff?) Can we do anything to prevent locked files, or is it simply part of normal processes?

You get the gist. I'd like to clear this up so that I can proceed with merging duplicate vendors, so thanks in advance for your time and expertise.