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Question

I have 2 clients who have the exact same issue of the above with googleleads referring visitors to their site, using so much disk space, both sites I have not had an issue with up to now.One client had there site and obviously emails cut off,I had increased their allowance, their site is fine, but emails are still affected. Any idea as to why this is happening? The number of visitors to the site are not indicitave to so much disk space being used, including search spiders.