Backup vs Sync in GoodSync Wrong Choice Can Delete Files
The most common GoodSync accident is not a bug — it is one wrong click at job creation. A 2-way sync pointed at the wrong folder will delete files with complete confidence. Here is how it happens and how to make it impossible.
🎥 The video shows both job types being created — watch the difference carefully, it is the whole point of this guide
Ask in any support forum about lost files and this story repeats: someone created a Synchronize (2-way) job, one side of it was an empty or old folder, and GoodSync did exactly what it was told — it made both sides identical. Identical meant the full side got emptied to match. Nothing malfunctioned. The lesson is not that GoodSync is dangerous; it is that sync and backup are opposite promises, and GoodSync keeps whichever promise you actually selected.
Analyze preview — the screen that saves you, if you read it
report-final.xlsx — exists on Left onlyWILL DELETE FROM LEFT
client-data (folder) — exists on Left onlyWILL DELETE FROM LEFT
notes.txt — exists on Right onlyWILL COPY TO LEFT
☑ Job type: Synchronize (2-way) • Right folder was empty at first run
👆 An Analyze preview from a real accident pattern. Every red deletion is visible BEFORE the Sync button is pressed. If a first-run preview shows mass deletions, cancel — the job type is wrong.
1
What Each Job Type Really Promises
Backup (1-way) promises: the destination becomes a copy of the source. Changes travel in one direction only. The source is never touched by anything that happens on the destination side
Synchronize (2-way) promises: both sides become identical — the newest state wins in both directions, including deletions. Delete on the laptop, and the deletion travels to the desktop. That is correct behaviour for two working machines and a catastrophe for a backup
In a 1-way job there is one more switch — Propagate Deletions. With it ON, deleting a source file also deletes the backup copy. With it OFF, the backup side only ever grows — much safer for protection jobs
2
The Three Ways This Accident Actually Happens
The empty-folder sync — a brand new empty folder on one side, your only data on the other, job type 2-way. Sync makes them equal — by emptying the full side
The replaced-laptop sync — the old PC dies, a fresh PC with an empty Documents folder syncs first, and the deletion of everything is faithfully propagated to the server copy
The tidy-up deletion — you delete junk from the destination to free space, forgetting the job is 2-way. Next run, the same files vanish from the source too
Notice the pattern: in every case the user imagined a one-way flow while the job was set to two-way.
3
Safeguard 1 — Use 1-Way Backup Jobs for Protection, Always
If the purpose of the job is safety — this folder must survive if that PC dies — then:
Job type = Backup Left to Right, with the precious folder on the Left
Open Job → Options → General and uncheck Propagate Deletions. Now even a deleted or emptied source cannot erase the backup in the same run — deletions simply stop travelling
Accept the trade-off honestly: the backup folder will slowly collect old files you deleted on purpose. That is a small housekeeping chore, not a disaster
4
Safeguard 2 — Turn On Saved Versions of Deleted and Replaced Files
GoodSync can keep the files it deletes or overwrites instead of destroying them:
In Job → Options, enable the option to save deleted and replaced files — choosing more than the last version only, if your disk space allows
Those files land in a hidden history folder named _gsdata_\_saved_ inside the sync folder on the side where the deletion happened
This is your undo button. A wrong sync discovered within the retention period is recoverable file by file
Note: the fast no-state 1-way mode skips this safety net — do not use fast mode on jobs that protect important data
5
Safeguard 3 — Read the Analyze Preview Like a Pre-Flight Check
Before the first run of any new job, and after changing any job's folders, always run Analyze and read the result
Healthy first backup: hundreds of copies, zero deletions. Anything else means stop and think
Healthy regular backup: a handful of changed files. A regular job suddenly planning to delete 400 files is GoodSync telling you something changed — a wrong disk mounted, a folder moved, a drive letter swapped
When in doubt, cancel the sync. Analyze costs nothing; a sync you did not read is the only expensive button in the program
🔴 It already happened — what now? Stop. Do not run the job again, and do not write new data to either disk. First look inside _gsdata_\_saved_ on both sides — if saved versions were enabled, your files are there. Also check each PC's Recycle Bin. If neither has them, file-recovery software is the last resort and works best on a disk that has seen no new writes. This is exactly the accident the video warns about — watch that section before your next job.
🎥 Watch the Complete Video
Watch the video's job-type section before creating your next job — it shows the exact moment where this choice is made.
I want deletions to reach the backup so it stays an exact mirror. Is that wrong?
It is not wrong, it is a choice with a price. Propagate Deletions ON gives you a clean mirror, but the mirror copies your mistakes in the same run — including accidental deletions and ransomware encryption. The safer pattern is deletions OFF plus saved versions enabled, and a periodic manual cleanup of the backup side when you are sure the deletions were intended.
Does a 2-way sync job count as a backup?
No. A 2-way sync is one logical set of data living in two places — delete or corrupt a file and both places follow. A backup is a separate copy that does not follow the source's bad day. Many offices run both: 2-way sync between two working PCs, plus a 1-way backup job from one of them to an external disk or cloud.
Where exactly does GoodSync keep deleted files?
In a folder called _gsdata_\_saved_ inside the sync folder, on the same side where the file was deleted or replaced — provided the save deleted/replaced files option was enabled for that job. The files sit in subfolders so you can find the version by date and copy it back by hand.
This guide is based on the Technical Anshu GoodSync Explained video • Stuck on any step? Ask in the video comments — you will get a reply there 🙏