A new computer is the most common moment when people lose data. Not through failure — through haste. The old machine is sold or moved to the basement, and two weeks later it turns out it held scanned documents or years of email.

One rule for the whole move: do not wipe the old disk until the new computer has worked for at least two weeks without a missing file. It is the cheapest insurance you have.

Step 1: make a list before you copy anything

Go through the old computer and write down what is genuinely needed. There is usually less of it than expected — and it sits in different places than intuition suggests.

  • Documents, desktop and the downloads folder — where important files usually land.
  • Photos and videos, including those inside editing software folders.
  • Email, if the program downloaded messages and deleted the server copy (POP3).
  • Passwords saved in the browser, plus bookmarks.
  • Application databases: accounting, warehouse, industry software, projects.
  • Licences and keys, usually in emails from years ago.
  • Electronic signature, banking certificates and configuration files.

Step 2: move data starting with what matters most

Ways of transferring data
MethodBest whenWatch out for
External driveLarge photo and document collectionsCopy, but do not delete the source yet
CloudCurrent documents, work on two machinesVerify the sync actually finished
Local networkVery large volumes, both machines at handA cable is faster and safer than Wi‑Fi
Old disk in an enclosureWhen the old computer no longer startsData is usually recoverable despite a broken system

Step 3: email — where things go missing most often

If you use webmail or IMAP, messages live on the server and appear once you sign in on the new machine. If your mail program used POP3, the messages exist only locally — you must move the whole program profile, not just “the inbox”. That distinction explains most calls of the “all my email disappeared” kind.

Step 4: passwords and access

Export passwords from the browser or move your password manager database. Before handing the old computer on, sign out of every account and clear saved sessions. Check two-factor authentication too: if codes come from an app on the old device, move it before wiping — otherwise regaining access can take days.

Step 5: the first week on the new machine

  • Open every program you use and confirm it sees its data.
  • Print something — the printer is the classic forgotten item.
  • Test scanning, the electronic signature and banking sign-in.
  • Set up a backup before you start creating new files.
  • Only after two weeks consider wiping the old disk.
Before selling the old computer: deleting files and formatting does not erase data permanently. The disk must be overwritten or removed — especially if it held documents, scans or company data.

When to hand it over

The move is simple as long as everything works. Help is worth it when the old computer will not start, when the disk holds industry application databases, or when a business is moving — a mistake then means downtime, not just a lost afternoon.

To be sure nothing is left behind, see computer repair and setup — configuring a new machine and transferring data is one of the most frequent jobs I do.