It depends on the version your client is using. The 2017 accountants version can open a file from 2016 & 2017 but can’t open a file from 2015 & prior.  So it can open current version & 1 year back.

Resolution for '2015 prior issue: 'Accountants copy transfer file' available: Yes.

The 2015 prior 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 2015 prior issue yourself by looking for a resolution described in the article. If it is a complex 2015 prior issue or you are unable to solve the issue, you may contact us by clicking here or by using other 2015 prior support options.

For more information about resolving issues related to 2015 prior in Quickbooks/QBO or to get support for the issue 'Accountants copy transfer file', click the link below: