sai
To restore a deleted company in Tally, you need to access the data folder where the company files are stored. Locate the company file with the extension .TSF (Tally Software File) or use the backup file if available. Rename the file to have a .DAT extension, then restart Tally to see the restored company in the company list. If you have a backup, you can also restore it by using the restore option under the 'Gateway of Tally'.
sattu
There is list of programs that support DO file extension http://www.howopen.org/en/extensions/web-files/do
Just go to the data subdir under the tally subdir & delete all the files
tally7.2accounts download support files
.XLS files are standard Microsoft Excel spreadsheet files. .XLT extension is used for the Excel template files. - Neeraj Sharma
Picture files no matter name they have they will definitely have an extension like xx.jpg . bmp and may more. window automatically will search for these files extension if asked to do so.
.b is an extension for binary files mostly used by video game emulators... .b is also the extension for BASIC programming language source text files...
msc
.fla
.exe
A compiled Help File in Windows will have the extension .chp