Every forgotten Excel password has the same root cause: the password lived in exactly one place, a person's memory, and memory changes jobs, goes on leave, and forgets. The fix is not a better memory. It is a system: a password manager for your own files, and a sealed envelope routine for the office, so any file can be opened by the right people even when its creator is unreachable.
Prevention guides usually say use a password manager and stop there. That advice is right but incomplete for office files, because office files outlive the people who set their passwords. This guide covers both halves honestly: the personal habit that protects your own files, and the shared, old-fashioned, surprisingly robust envelope system that small offices have used for decades to make sure no spreadsheet is ever again locked by one employee's memory.
Password: stored here, shown only after your master password
Notes: set by Anshu, accounts office PC, file on the accounts share
Updated: when the password changes, this entry changes the same day
A password manager replaces dozens of fragile memories with one strong one. You remember a single long master passphrase; the manager remembers everything else, including every file password, recorded with the file's name so future-you can find it. Choose a reputable manager, protect it with a long passphrase you use nowhere else, and turn on its backup or sync so the vault itself is not a single point of failure. Then adopt the one rule that makes the system work: no Excel password gets set unless it is typed into the manager first. A password that exists in the manager cannot be forgotten, only looked up.
Offices need access to survive absence, and the classic answer is the sealed envelope. The file's password is written on paper, sealed in an envelope marked with the file name and date, signed across the seal, and kept in the office safe or with the owner. It is opened only when genuinely needed, in the presence of a second person, and the opening is written in a simple log: date, file, who opened, why. Then the password is changed, a new envelope is sealed, and the log notes that too. It sounds old-fashioned because it is, and it works precisely because it is physical, witnessed and logged. Writing a password down is not the sin people think it is; a sealed, signed, logged envelope in a safe is far safer than a password that exists only in the memory of someone who resigned in March.
Separate the two lock types in your system, because they carry different risks. A sheet protection password is low stakes: it can be shared with the team that maintains the file and recorded in the team manager or envelope without worry. A file-open encryption password is the key to the data itself: fewer holders, recorded more carefully, and changed whenever a holder leaves. Write down, for each important locked file, three things: the file, where it lives, and who can authorise opening the record. If that list cannot be produced for a file today, that file is one resignation away from becoming a recovery case.
Systems fail at handovers, so make the handover boring. When someone sets or changes a password on a shared file, the same day: the manager entry or envelope is updated, the owner of the file is told, and the change is noted. When someone leaves, their list of locked files is part of the exit checklist, passwords are rotated, and new envelopes are sealed. Once a quarter, pick two important locked files and prove the system works by opening them from the record alone. A password system that is never tested is a hope, not a system, and the test is what turns this guide from advice into insurance.
The video shows this recovery on a real file, step by step, including which password type it works on.
Watch Full VideoUncontrolled paper is a risk; a sealed, signed envelope in a safe, opened only with a witness and a log entry, is a controlled system that offices and banks have relied on for decades. Compare the realistic alternatives: a password forgotten entirely, or the same password reused everywhere so it can be remembered. The envelope beats both. The genuine rule is not never write it down, it is never leave it lying around unrecorded and unguarded.
Any reputable, actively maintained manager is fine; the brand matters less than the discipline. What matters is that the vault is protected by a strong master passphrase, backed up or synced, and that access for shared office passwords is granted deliberately, person by person, and removed when someone leaves. A shared spreadsheet of passwords, or passwords in a chat thread, is not a manager and should be retired.
Make an inventory first: list the locked files that matter, who set each password, and whether anyone can still open them. Recover or re-protect the ones you can, using the guides in this series where needed, and record every password into the new system as you go. Files nobody can open go through the honest recovery routes. Within one such pass, most offices go from memory-dependent to system-dependent, which is the entire goal.