(Errcode: 13)

Hello everybody,
I was creating a product and after validating i received this message:
1 Can't create/write to file '/tmp/#sql_21ff_1.MYI' (Errcode: 13)
in:
[select c.categories_id, cd.categories_name, cd.categories_description, c.categories_image, c.parent_id, c.sort_order, c.date_added, c.last_modified, c.categories_status from zen_categories c, zen_categories_description cd where c.parent_id = '0' and c.categories_id = cd.categories_id and cd.language_id = '1' order by c.sort_order, cd.categories_name]
Everything in my shop disappeared, I lost all my products.

What is that? Is there a way to resolve it?
I cannot believe this.
Thank you in advance!
v1.3.9g

yep. i'm getting the same message. From other posts that I've been reading and after speaking with my hosting company, it seems as if it IS something on their end. I will keep you posted as more info becomes available to me.