When a password for opening is set, the document's content is encrypted and cannot be viewed without the correct password.
If you encounter the enter password dialog (see below) when opening the document in Microsoft Excel, it means that the document is password-protected.
If an opening password is set, a strong encryption method is used, so the password generally cannot be recovered instantly. However, with Excel Password Recovery's unique methods, in most cases passwords are recovered very quickly.
The password to open a document will be recovered instantly if it was protected using weak encryption. This includes Microsoft Excel 95 (and older) documents, Microsoft Excel 97-2000 (on a computers with French regional settings) and Microsoft Excel 2003/2002 (XP) documents if the Weak Encryption (XOR) was used.
To set, modify or remove a known (or recovered) password for opening: