Locking the file was the easy half. The moment you send it, your careful password can be defeated by one careless habit: emailing the password in the same message as the file. This guide covers the sharing half of the job, so the lock you set in the video keeps its value all the way to the other person's screen.
The encrypted file itself travels well. It can sit in an inbox, on a pen drive, in a shared folder, and show nothing to anyone without the password. The weak point is never the file; it is the password's journey and what happens after the right person opens it. Four habits decide whether your locked file stays locked in practice.
Send the file by one route and the password by a different one: file by email, password by phone call or a WhatsApp message; file on the shared drive, password spoken in the room. Never write the password in the same email as the attachment, never in a follow-up in the same thread, and never in the file name or a document inside the same folder.
The reason is simple. Mailboxes are what actually get compromised, forwarded and left open on shared PCs. A locked file in a stolen inbox is a dead end. A locked file in a stolen inbox whose password sits two messages below it is not locked at all.
Half the support calls about shared files are confusion, not failure. Before sending, say plainly what to expect: the file will ask for a password before it opens, because it is encrypted, and the password is coming separately. If you also set a Password to modify, warn them about the read-only prompt, or better, for a file you are sending out to be read, leave the modify box empty so nobody meets a second, pointless prompt.
Also say what the password is not: not their email password, not to be typed anywhere except that Excel prompt, and case-sensitive exactly as sent. Sending it as clean typed text rather than a photo of handwriting prevents most failed first attempts.
Be honest with yourself about the boundary of the lock. It controls the file. Once your receiver opens it with the correct password, they can save an unprotected copy, print it, or forward it together with the password, and Excel will not stop them. That is not a flaw; no file lock can police a person you chose to trust.
So choose the circle by the data, not by convenience. If the file is so sensitive that a careless forward would be a disaster, a locked attachment may be the wrong tool entirely, and a view-only shared link with an expiry, where the data never becomes a free file, is the safer route. The lock is for files that must travel but only be read by the named few.
Offices often lock every month's file with the same password forever, which quietly widens the circle to everyone who ever received any month. Better habits cost nothing:
If you are the one receiving locked files, hold up your side. Save the password into your password manager the moment it arrives rather than leaving it in the chat or inbox. Do not forward the file and password together when you pass work along; send the file and tell the next person the password will come from the sender or by a separate message. And when you keep a local copy, keep it locked: save your working copy with the same open password, so the data is not sitting unprotected on your disk because of you.
The video sets this password on a real Excel file in about a minute, including the confirmation step and the save.
Watch Full VideoIt is a different channel from email, which is the main point of the rule, and for ordinary office files it is a reasonable choice. For highly sensitive data, a phone call is better still, because the password is spoken and never sits in a chat history that gets backed up, screenshotted or forwarded.
Most often a capitals mistake, because Excel passwords are case-sensitive, or an extra space copied from the end of a chat message. Less often, they are typing the password into a modify-password prompt or a different file entirely. Walk them through opening the exact attachment fresh and typing the password by hand.
Treat the password as spent. Re-save the file with a new Password to open (F12, Tools, General Options), resend the file, and send the new password by the second channel. Tell the receiver to delete the first copy. The old password is not a disaster if the mail stayed inside the intended inbox, but it no longer counts as protection.