Files with 1txt suffix can be typically encountered as encrypted and renamed archives affected by the Enigma ransomware.
1TXT file extension - Enigma ransomware affected file
What is 1txt file? How to open 1txt files?
File type specification:
File extension 1txt seems to be related to a variant of Enigma ransomware that switched in late October 2016 to 1txt suffix.
Much like other similar ransomware, it encrypts and renames users documents and other personal files and then demands ransom for the decryption key.