Q: Recently, after I had replaced my hard disk which had crashed with a new one, I realised that many of my PowerPoint and PDF files had changed to ppt.rxf and pdf.rxf respectively.

I am unable to open the converted files. Is there any free software available to convert these files back to their original formats?

Calvin Lim

A: It is likely that your computer has been infected by some malware or ransomware. The latter disguises itself as a useful utility program, like something to recover lost files or fix corrupted hard disk drives.

When you unsuspectingly run this software, it encrypts all your user files. The next time you try to open the files, you will probably receive a message indicating that they have been encrypted and you must contact and pay a fee to have them released.

A quick search on the Internet revealed that there is a program to repair "Recipe Exchange Format" corrupted data files at this website.

The website is called Corrupted Data Recovery (http://www.corrupteddatarecovery.com/Repair/ Recipe-Exchange-Format-File-Repair-RXF-Data- Conversion.asp)

Try contacting the company as they indicate that no fees will be charged unless recovery is possible.

Give them a file which you cannot open. If they are successful and then ask for exorbitant fees, I would suspect that you have been a victim of ransomware.

Please ensure that the file you cannot open does not contain sensitive or private information.

Answer by Chester Chen and MK Wong. Chester is a recognised Microsoft Most Valuable Professional specialising in Windows desktop experience. MK Wong is an IT lecturer.

This story was first published in The Straits Times Digital Life.

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