Right click the Tally shortcut in the Desktop, goto properties, Copy the Tally .exe path which is in the Target Box. (for e.g C:\tally.erp9\tally.exe)
Then --> goto Start--> Run--> Paste press space and type the Tally full data path and press space 0 (C:\tally.erp9\tally.exe C:\tally.erp9\Data 0).
When tally opens, press ctrl+alt+R.
Choose the company that you are getting the error msg.
After rewirte process completed your problem solved.