The files will move in a weekend. The people will take a month. This page plans for both — the data transfer, the format questions, and the habit changes that decide whether the migration sticks.
Every migration guide obsesses over moving files, because files are the measurable part. Files are also the easy part. The migrations that fail, fail in week three, when staff quietly drift back to emailing attachments and keeping private copies "just in case". Plan the human migration with the same care as the data migration and the move sticks.
Files move in days. Habits move in weeks. Plan for both clocks or the old system never dies.
Spend one meeting on three lists: what data exists (and how much of it is junk nobody has opened in three years — migrations are the perfect excuse to not carry it), who shares what with whom outside the company (external shares must be recreated, and clients informed), and what must not move (email stays put, per the standing rule in this series). Decide the group and folder structure now — the structure guide in this series — because structure decided mid-migration gets decided twice.
Download or sync the data department by department into the matching group folders, ideally in the evening or over a weekend, then verify with counts and spot-checks before declaring each department done. Move a pilot department first — the friendliest one — and let them work for a week. Their complaints are your free quality check; fix the structure and permissions while the blast radius is one team, not the whole company.
Google Docs, Sheets and Slides are not files in the usual sense — they export to docx, xlsx and pptx, and most documents survive the conversion cleanly. The honest exceptions: heavily formatted documents may shift a little, Google-specific functions in complex Sheets sometimes have no twin, and files that were "links to other files" inside Google’s world arrive as ordinary copies. Microsoft 365 files barely notice the move, since OnlyOffice works in their native formats. Either way: keep the old system readable for a month as the reference copy while formats are proven in daily work.
Set a date when the old drives become read-only, and a later date when the old licences are cancelled. The read-only step is what forces the last stragglers across; the cancellation is what turns the migration into savings — plenty of offices run both systems for a year "temporarily" and pay for the privilege. Keep an exported archive of the old system for records, close the accounts, and let the finance team see the cancelled bill. That email is the migration’s real finish line.
See the destination system running in the video above — it helps staff picture what they are moving to, which is half the battle.
Watch Full VideoFor an office of 10 to 30 people: roughly two to four weeks part-time, including the pilot week and the parallel-run period. The file copying itself is usually a weekend. Compressing the human side below two weeks is where migrations get their scars.
Yes — Google or Microsoft sharing links die with those accounts. List your external shares in the audit phase, recreate the important ones as Nextcloud links with passwords and expiries, and send clients one tidy email with the new links before the old ones close.
Partially, and it is a common pattern: keep mailboxes on a Google or Microsoft email plan, or move email to a plain business mail host, while files and documents live on your Nextcloud. You stop paying for the storage-and-apps bundle, which is where the growth was.