XML files do not open

[Joeboy]

I am posting this question again.  I created several Mathcad files (using 15)  last year.  I tried to open them yesterday.  I got a message saying "not a valid XML file"  .   Then I tried to attach the offending file and it would not attach, saying "file contents do no match file type".   Can someone out there explain what is going on and how to correct this.   Has PTC developed a fix for the problem?  My email address is dmgjr@suddenlink.net 

[Werner_E]

> I am posting this question again

Yes, and I am posting this answer again for the third time.

The file you posted twice in the other two threads of yours is damaged and can't be repaired. There is not information stored in it anymore.

I am working with Mathcad for a very long time with various versions of Mathcad and it (fortunately) never happened to me. So I can't even guess what the cause may be. I am not sure if could have been Mathcad which damaged the file while saving - chances are it didn't, otherwise other people would have told about the problem here, too.

[Joeboy]

I began using Mathcad long before it was taken in by PTC.   Version 1.5 I think, around 1999 I think

[Werner_E]

---

@Joeboy wrote:

I began using Mathcad long before it was taken in by PTC.   Version 1.5 I think, around 1999 I think

---

OK, so you beat me 😉

My first was DOS version 2.0, followed by 2.5.

[VladimirN]

And what was the reason for this choice at that time?

[Werner_E]

---

@VladimirN wrote:

And what was the reason for this choice at that time?

---

Units, math-like notation and ... curiosity, I guess.

[tietjee]

If you have maintenance, try having Mathcad solve the problem.  I have little luck with there support, but it is nice to send a puzzle.