You’ll find that many Frequently Asked Questions (FAQ) are in the various forum FAQs – and we have one that talked about the C0000005 error in this Reporter FAQ.
Also – you’ll find that Search is Your Friend here on BOB. Try searching with a few keywords that are similar to your question first, and you may find that this has been discussed in the past. A good search word in this case could have been c0000005.
And then, if none of the past posts help – you’ll need to get more specific when you ask for help. What version are you using? What module (Reporter, Designer, Supervisor…) were you using? What were you doing? Is it repeatable? What else was going on? Did something recently change on your workstation (e.g. upgraded operating system, or applied a service pack to something, etc.)…