Why do I get an 'access is denied' error when starting a build?
 

The user account (or the group the account is in) that Visual Build Pro runs under must have DCOM permissions to access applications (this is enabled by default, but if your computer's configuration was modified this error could occur).

Running dcomcnfg will launch the Component Services Explorer. Expand Component Services, then Computers, right-click on My Computer, choose Properties, and go to the Default COM Security tab to edit the access permissions.

It may be necessary to restart for the changes to take effect.