Macro Is Unlocking Locked Cells

I'm using three different workbooks for the macro I've designed. The macro works exactly as I planned it would, but I'm getting a curious side-effect of running the macro. I have over 5,000 workbooks that I need to open, unprotect, change (mostly by copy/paste), and reprotect. It's a fairly straight forward macro, but it is my first, and I must be overlooking something. When the macro is complete, cells that were not modified via the macro in any planned/anticipated way are being unlocked. This has left me puzzled and frustrated. The files are opened, unprotected, the cells are copied over as planned, reprotected, and closed/saved. Everything works perfectly, but the cells in parts of the workbook (Filename) (which were locked before the macro ran) have been unlocked and are no longer protected when the workbook is reprotected. Again, these cells were not within the ranges modified, and I'd rather not have to format every cell in every one of the 5 sheets of (Filename) to be locked.

File names are:
"Finished Goods Inventory TREE (ToDMSI).xls" (alias: Workfile - sheet providing file path to be updated)
"Random_workbook_selected_from_previous_filename.xls" (alias: FileName - the copy-to file being updated)
"MACRO TEST BOM Master.xls" (the copy-from file always open)

Comma Delimited table layout in "Finished Goods Inventory TREE (ToDMSI).xls":
Col A, Col B, Col C, Col D
Customer ID,Item Code,File Name, Directory
4FRE01,4FRE01-0001,4FRE01-0001.xls,4FRONT

Here's the



Public FileName

Public Workfile

Public ItemCode

Public CustCode

Sub OpenBOMSeq()