I see a lot of posts about writing to the SD card, but I believe my problem is different. I am unable to create the SD card during the process of building an AVD.
I
I had the same error like you and I have just solved it, so maybe it can help you (though I don't think your error is caused by the same problem like me).
I found that all tools in ../tools don't have the permission to excute, so I used
chmod -R 777 ../tools
from the command line and it finally works