Tally data recovery — recover corrupted .tcp backup files in India

Why does Tally data get corrupted after a power cut?

Short answer: Tally ERP 9 and TallyPrime keep their company data in a set of proprietary database files that are constantly being written during an active session. A sudden power cut mid-transaction leaves these files in an inconsistent state — partially written records that Tally cannot parse on the next launch. The result is the dreaded “Data file corrupted” or “Company list empty” error. The accounting data is usually still on the drive — it just needs a specialist to extract and rebuild it.

How to approach Tally data recovery

Step 1: Locate your Tally data folder and check what you have

Before calling anyone, locate your Tally data folder. In TallyPrime, press F1 (Help) → About, and look for the “Data Directory” path. In Tally ERP 9, it is typically C:\Tally.ERP9\Data\. Each company has a numbered subfolder (10001, 10002, etc.) containing several files: Manager.900, Company.tsf, and voucher files. Check whether any .tcp backup files exist in the same folder or in a separate backup location configured in F12. If you have a recent .tcp backup, the recovery is straightforward — restore it to a fresh Tally installation on a working machine.

Step 2: Attempt the built-in Tally repair utility

Tally has a built-in data repair function. Launch Tally, press F3 (Company) → Alter, select the corrupted company, and look for the Rewrite option (in Tally ERP 9: Gateway of Tally → F3 → Rewrite; in TallyPrime: the data repair option is under Help → Troubleshooting). This rewrites the data files using any intact transactions it can find. It succeeds in 60–70% of minor corruption cases caused by clean power cuts. If the rewrite fails or Tally cannot open the company at all, move to professional recovery.

Step 3: Extract from .tcp backup using archive tools

A .tcp file is a compressed archive — it can be opened with 7-Zip (free) or WinRAR. Change the extension temporarily to .zip and attempt to extract. If the .tcp file is undamaged, you will find the company’s .tsf and .900 files inside. Copy these to your Tally data directory and reopen Tally. If the .tcp file itself is corrupted (the power cut happened during the backup write), archive repair tools like DiskInternals ZIP Repair can attempt to salvage the inner files. See our broader guide on why backing up before any repair matters for context on data hygiene.

Step 4: The India angle — power grid and Tally data loss

Tally is used by more businesses in India than in any other country — and India’s power infrastructure makes it particularly vulnerable. Cities like Hyderabad, Pune, and Lucknow still experience 2–6 power interruptions per week in commercial zones. Tally’s data files are written frequently and synchronously — meaning there is no background commit cycle that protects recent data during a power event. A UPS rated for at least 600VA (VA = volt-amperes, the unit for power rating) gives approximately 10–15 minutes of runtime for a desktop running Tally — enough to save and close gracefully. Cloud-based TallyPrime on AWS or Azure eliminates this risk entirely, but costs more per month than most SME accounting setups budget for. See the bench stories of Tally data loss cases we have handled for real-world examples.

When DIY ends

Stop self-recovery attempts if: Tally’s built-in rewrite utility crashes mid-process; the data folder files are missing entirely (the drive may have a file-system issue); the company list shows the company but opening it produces a blank ledger; or the hard drive makes any unusual sound. In these cases, a professional data recovery service can extract the raw .tsf and .900 files directly from the drive’s sectors — even if Tally cannot open them — and reconstruct the database.

Typical recovery cost in India

Professional Tally data recovery — reconstructing corrupted data files, restoring from a damaged .tcp backup, or extracting files from a failing drive — costs ₹2,000–₹6,000 for logical recovery in India. Physical drive damage raises this to ₹8,000–₹25,000. Many chartered accountants and SME businesses across India ship drives to our Secunderabad lab and receive recovered data within 3–5 working days. Visit our professional data recovery service page to start a recovery.

A note from the LRW Engineer Team

The costliest Tally recoveries we see are cases where the business owner reinstalled Windows or formatted the drive “to start fresh” before checking whether recovery was possible. Formatting overwrites Tally data files with zeros — permanent loss. If Tally is showing errors, the very first step is to copy the entire Data folder to an external drive before doing anything else. That one action takes five minutes and has saved hundreds of businesses from catastrophic accounting data loss.