Wahay! A Name check! Thanks Daz!
Sorry to hear about the problems mate. Just in case you don't know, Error 99 indicates a hardware incompatibility, though quite why it would work once and then not the next is beyond me.
I've not experienced this problem myself but have just googled for the problem and you're not alone! This site
has some blogs of people with similar problems... maybe one of them has a fix?
It seems to boil down to Sigma not paying royalty fees to make EF
lenses and having to reverse engineer them. Sometimes when a new body comes out they are caught short on the specs.... apparently!
Out of interest is the BIGMA new or S/H? One of the bloggers mentions having Sigma change the electronics in his BIGMA to get it to work.
Hope this helps and I hope you get the problem fixed soon!
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