Images issue

I keep forming Gallerys to my website, however, after uploading some images suddenly wordpress decides to stop working and presents me with this

‘The uploaded file could not be moved to /home/kashame/public_html/wp-content/uploads/2011/03.’

Can anyone please help me out? I’ve tried EVERYTHING. Re-installing, adding bits of code as suggested, and a few other ‘solutions’.

Any help appreciated.

Thank you,

Kasha