Sometimes, when you try to delete a large number of rows from a table the transaction file may grow to the point that you will run out of disk space. In other occasions, when the transaction log growth is limited, the delete can fail with the following message:
The transaction log for database ‘database name’ is [...]

If you noticed that the free space on your hard drive is shrinking and you found that the log LDF file is taking most of it (and growing) don’t panic.
it is possible that the reason is that your recovery mode is is set to full.
to change this:
1) Right click on the db (in SQL server [...]