Obsolete File extensions for Blocks 90's era

[darvin.carlson]

The old timers have retired. There is a subdirectory under our Blocks directory that contains what appears to be block-associated file with a .INF extension and file dates around 1992. Some but not all have a same name .ATT file. Almost a certainty that these are obsolete. Can't find any info on the web. Anyone know what these extensions represent? The file names don't align with our current blocks but hate to delete something that might be needed to open an old file (but highly unlikely).

[TheCADnoob]

can you open the inf file in a text editor to see if you can get any more information?

[pendean]

Why not test it out: backup those folders, delete those unknown files, see what happens. You can always put them back later.

TLDR? trash them.

[paullimapa]

Back in those early DOS days you can name files with practically any extensions you like and that includes text files. So try opening these with Notepad and see if they are legible 

[darvin.carlson]

When opened in Notepad ,both types appear as "machine language"....similar to what I used to experience when I would send a postscript file to an HPGL printer. The .INF may be echoing some type of a dialog box as the snippets of readable text appear to have layer attribute headings (layer/color) and one of the readable strings in the midst of machine characters was "Were Other Wblocks used to create this block". The ATT files are similar in appearance, but the specific one I looked at (that paired with the same name INF) had less readable text. My guess is these were some sort of default extensiosn in a VERY old version of AutoCAD. These files predate widespread use of the web which would limit information that's available....unless I can find a very old AutoCAD textbook. As stated...99.99% probability of useless.

[paullimapa · Accepted solution]

I don’t recall any AutoCAD DOS releases using any of these types of file extensions. Perhaps it might have been a third party app. I would say it’s safe to trash them