1. Take a backup of the Tally data.
Do a manual backup of the Company giving the error.
2. Disable auto loading of Companies
Set Gateway > Configure > Data Configuration > Load Companies on start-up = No
This can also be changed by editing the ini configuration file.
3. Open Tally in debug mode from the Command Prompt
Start > Run.
Type - Path\To\Tally\Executable Path\To\Tally\Company Error\Id\No
Example - (C:\Tally.ERP9\tally.exe D:\Data\10001 2517)
4. Rewrite the problematic Tally.ERP9 company
Rewrite by Ctrl+Alt+R from the Company Info screen and selecting the problematic Company.
Select “Yes” to rewrite the data.