My memory pen won't let me transfer files between home and work, help!

[cathcat]

I have a newish memory stick/pen and it was working fine. then something must have happened because anything I have done at home, since last Wednesday, will not open at work - a message comes up saying the file needs a converter (but if you say yes to this it then cannot find whatever it is looking for to convert it) and if you say no you get 26 pages of gibberish.
I know this is a bit random but please if anyone can help I'd be really grateful. TIA.

Do a virus check. There is a very virulent virus going around that is transmitted via memory stick. We had it at school and were not able to do IT lessons for the best part of a week.

Are they Word files?
Do you have Word 2007 at home and 2003 at work?

Or if they are other files, what type & what progam do you usually ue to open them?

They are just ordinary word files.
I am not sure which version we have at work and home, the one at work is quite new and has Windows XP, as do I at home. I didn't have any problem until last week which makes me think I have changed a setting somewhere without meaning to or my pen is corrupted in some way - but then surely nothing would open. Everything made before last wednesday is fine.

If you have Word 2007 at home and save documents just as 'Word Document', it saves with .docx at the end of the filename, and Word 2003 can't open it without a file converter. (Word 2003 and before saves with .doc at the end)
If you save the documents in Word 2007 as 'Word 97-2003 document' which is the 3rd option down, then you can open them in Word 2003. It's possible that you were doing this up until Wednesday, but the ones since Wednesday were saved in the new format.
If this is what's happened (and it may not be) the file converter you need is this one. You can download it at work, if you're allowed to download files, or you can save it on your USB drive (the memory pen)and install it at work (but you may need permission from your tech people if you have any.)

If you look at the files on your USB drive in My computer, you may be able to see what the letters at the end of the filename are (it's called a file extension), but it's often hidden. This page tells you how to see them

thank you RB that looks very useful. I'm away to try it now. So helpful, many thanks!