Isn’t there a file with the same name as the file with the .DBT extension but with an extension of .DBF somewhere near? The .dbt file is a memo file associated with a .dbf (dBase, Foxpro) database file. If you already have any application which will open this type of file. E.g., foxpro, dBase, Access etc. You can open the .dbf file and the application will automatically extract from the .dbt file the corresponding data. If you do not have the .dbf file then it is a little bit more complicated. The .dbt structure is basically flat text, with some pointers in it relating to the records in the original .dbf file. You can open this using notepad and extract the text which is stored in it quite easily but without the original database you do not know to which records it refers.
If.dfb file not opened or corrupted, you can use a DBF Recovery Toolbox. Maybe you will solve the issue that way.
http://www.oemailrecovery.com/dbf_recovery.html