See this support article, http://qblittlesquare.com/2012/12/sharing-your-quickbooks-file-across-networks/

Resolution for 'Book remotely issue: 'May i work on my clients Mac Book remotely?' available: Yes.

The Book remotely issue or error code is a known issue in Quickbooks Online (QBO) and/or Quickbooks. Support for this issue is available either by self-service or paid support options. Experts are available to resolve your Quickbooks issue to ensure minimal downtime and continue running your business. First try to resolve the Book remotely issue yourself by looking for a resolution described in the article. If it is a complex Book remotely issue or you are unable to solve the issue, you may contact us by clicking here or by using other Book remotely support options.

For more information about resolving issues related to Book remotely in Quickbooks/QBO or to get support for the issue 'May i work on my clients Mac Book remotely?', click the link below: