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File Format
Extension(s) .bts
Released ≤1998

BTSPK is a compressed archive utility for DOS, and its associated .BTS file format. It was developed by Big Tree Software (contact: J. Hidasi). One of its main features is encryption.

The unregistered version, at least, seems to be more interested in deleting data than in archiving it. It tries to only allow decompression for up to 5 days after an archive's creation. Its documentation even warns "I'm not respectful for data lost!".

Format details

For v3.60b at least, a BTS file starts with a segment in standard ARC format, containing a registration form and other data. The main part of the archive follows, in a format that begins with the byte 0x1b. (Note some similarity to ArcMac.)


[More research may be needed. Only v3.60b has been evaluated.]

A file beginning with bytes 1a 03, then "Descript", could be BTS, though it could also be a pathological ARC file.

BTS files possibly always end with the following 31 bytes, containing the strings "MASTR" and "END!!!!".

1b 03 4d 41 53 54 52 ff 45 4e 44 21 21 21 21 00
00 00 00 00 00 00 00 00 00 00 00 00 00 1a 00


  • BTSPK 3.60b BETA_1 - Warning: This software may delete your data, instead of extracting it. Make sure you have backup copies.
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