Your file does not contain Gujarati. It contains English letters, and a font that draws them as Gujarati. Here is what that means and how to fix it.
You open a notice you typed in 2004. Instead of Gujarati you get something like “mih!. s|rtinii miI a!d&.” — English letters, punctuation, nonsense. The document looked perfect on the machine it was written on, and it looks like this everywhere else.
Nothing is corrupted. The file is doing exactly what it has always done. What has changed is the computer reading it.
Before Unicode was widely supported, Gujarati was typed using fonts that replace the English alphabet with Gujarati shapes. Press the “k” key and the file stores the letter k. The font is what draws a ક on screen.
So the Gujarati in those documents was never text. It was a drawing instruction. The text underneath was always English letters, and it still is.
This is why the same file opens correctly on an old office machine and as nonsense on a new laptop: the old machine has the font installed, and the new one does not.
Installing the typist font does make the document readable again, and if all you need is to read it once, that is the fastest answer.
It does not fix anything else. The text is still English letters as far as every other program is concerned.
Converting to Unicode replaces those English letters with the real Gujarati characters. After conversion the document contains ગુજરાતી as text — searchable, copyable, and readable on any device without installing anything.
The conversion is a lookup: this byte in this font means this Gujarati letter. That table has to be built and verified for each font family, which is why no tool converts every font ever made.
If you only have a paragraph, paste it into the free converter — it runs inside your browser and nothing is uploaded.
If you have the whole file, the signed-in converter reads the .doc or .docx directly, works out the font from the file itself rather than asking you, and returns a Word document with its tables, headings and numbering intact.
Paste a paragraph into the free converter — it runs in your browser and nothing is uploaded. For a whole file, with its tables and formatting intact, use the full converter.