Files with pgn file extension can be found as special TIFF images used by Picatinny Arsenal Electronic Formstore. Just rename it back to TIF.
There is one other file type using
the PGN file extension!
.pgn - Portable Game Notation format
PGN file extension - Picatinny Arsenal Electronic formstore data
What is pgn file? How to open pgn files?
File type specification:
The pgn file extension is used for a TIFF file format used by Picatinny Arsenal Electronic Formstore.
Tagged Image File Format - one of the most widely supported lossless (does not lose information during compression) file formats for storing bit-mapped images (both PCs and Macintosh computers).
TIFF graphics can be any resolution, in black and white, gray-scaled, or color. Is used un-compressed or LZW compressed.
Many different formats (Uncompressed, Huffman compressed, Jpeg,CCITT3/4, G3 FAX, G4 FAX, Packed Bits).
MIME types:
application/formstore
This pgn file type entry was marked as obsolete and no longer supported file format.
This type of file is no longer actively used and is most likely obsolete. This is typically the case for system files in old operating systems, file types from long discontinued software, or previous versions of certain file types (like documents, projects etc.) that were replaced in higher versions of their original programs.