The case of the read-only USB sticks.

[Hendrik Boom <hendrik@topoi.pooq.com>]

I have a problem with my USB sticks mysteriously becoming read-only.

I decided to investigate. I bought three identical 8G USB sticks, 
identical except for colour).  None of them appear have any switches on 
them.

The first I used my Linux laptop to write a file into the top-level 
directory of the first stick:  I mounted it, wrote it, and unmounted it.  
I handed it to my wife, who was to read it on her Mac.  She told me it 
failed to even notice there was a USB stick plugged in.  But returned to 
me, I could mount it and read it.

I put the second into my Linux laptop, mounted it, listed the top-level 
directory (it was empty), unmounted it.  I passed it to my wife, who 
plugged it into her Mac, and it immediately noticed the USB stick and 
allowed her to look at its contents.  It was, of course, empty.

I'm running Debian testing on an ASUS netbook.

Speculation: 

Now this doesn't tell me anything about how my USB sticks turn read-
only.  But it does tell me that something weird is happening to them.  
Perhaps the two OS's have different ieas as to how USB sticks are to be 
written or read?  Perhaps one of the other machined in the house it 
writing the in such a was that Linux can't read them?

What do I need to know to investigate this.

Has anyone else had problems like this?

Online all I found was some people on Windows with read-only USB sticks.  
One of them said that some friend using Linux had "fixed" them.  No one 
else had any luck.  I have no idea if their experience has any relevance.

-- hendrik