By courtesy of WhiteHatXL, I reproduce part of his review dedicated to LockXls
PROS: The tool is programmed in C++. In protected solution everything works like in original workbook. Average user cannot see formulas in cells and vba code in protected workbook. Protects xla files. Lots of features.
CONS: The product uses unmodified, original workbooks in protected solutions and relies on hackers’ methods to take customer away from seeing the content of the workbook (Hooks Excel windows and blocks Excel’s COM objects methods calls). The tool is trying to stub all Excel’s security breaches, which is impossible with an unmodified, original workbook.
When a protected solution has been started on an end customer computer, the spreadsheet becomes as unprotected as newborn baby.
5 lines of C code extract the original workbook from the protected solution, doesn’t matter whether it’s xls or exe file.
To prove the vulnerability of LockXLS solutions, just e-mail a protected solution to WhiteHatXL at yahoo dot com , the original workbook will be returned.
SUMMARY: Fake. This product is not for a workbook protection.
The full review you may find here http://sites.google.com/site/whitehatxl/
or here as an image http://i.imgur.com/8JJeQ.png