Storage versus synchronisation
A synced file can appear on several devices. Deleting it on one device may delete it everywhere.
Cloud storage versus backup
Some services keep deleted versions for a period, but cloud synchronisation should not be your only backup for irreplaceable files.
Internet and storage limits
Uploading needs internet access and enough account storage.
Account security matters
Use a unique password and Two-factor authentication: An extra sign-in check, such as a code or app approval, used in addition to a password. Full definition because the account controls access to the files.
Check status icons
A cloud icon, tick or warning can show whether a file is online-only, downloaded or failing to sync.
Keep another copy
Important files should also exist on a separate checked backup.
Still stuck?
Social Blade IT Services can help onsite or remotely. We explain the next step before extra work or parts.