The export worked perfectly. That is exactly when this mistake happens - both PCs carry on typing into the same company name, and within a week neither set of books matches the other. This is the warning to read before that happens.
Of every problem in this series, this is the only one caused by success. The backup restored perfectly, the company opened, the totals matched - so both offices relaxed and kept working. But a restored backup is a fork: two independent databases that will never reconcile on their own. Here is how the divergence happens, how to decide ownership before you export, and what to do when you actually need shared live access.
A restored backup is not a linked copy. From the moment of restore, the two databases live separate lives.
Tally has no built-in merge for two copies of the same company that have both been edited. The sync features people hear about work between an online and offline copy managed by Tally's own synchronisation setup from the start - they do not rescue two independently restored backups after the fact. If both PCs type entries after the export, there is no button that combines them. Someone ends up re-entering vouchers by hand, or one side's work is thrown away.
The handover conversation needs one clear answer: after this export, which PC is the live company?
If the client and the accountant both need to work in the same company regularly, keep one copy of the data on one machine and give the other side access to it: Tally's own remote access features, a shared network in the same office, or a remote-desktop style setup where the second person works on the host PC. One copy means one truth - every voucher exists once, and both sides always see the same Trial Balance. The moment a second copy is restored "just for convenience", the fork problem starts again.
Stop both sides entering for an hour. Compare the Day Book on both PCs from the export date forward and list which vouchers exist in only one copy. Pick the copy with more work as the master, re-enter the missing vouchers into it from the other, verify the Trial Balance, and then freeze the losing copy permanently. It is dull, manual work - which is exactly why the decision in step 2 is worth two minutes before every export.
Backup, transfer and restore shown live on screen, with the full knowledge and installation details.
Watch Full VideoThere is no built-in merge for two independently edited copies. The practical recovery is manual: pick one copy as master, compare Day Books from the export date, and re-enter the vouchers that exist only in the other copy.
Yes - a view-only copy is safe as long as it is clearly marked as an archive and nobody enters vouchers into it. The danger is not the copy existing; it is both copies being edited.
Keep one live copy on one PC and give the other side access to that same copy - Tally remote access, a shared office network, or a remote-desktop setup. One copy means both sides always see identical books.