Please note that Windows Server 2012 R2 is supported OS for QB 2014. See the link below to check the other system requirements for QB 2014:

http://support.quickbooks.intuit.com/support/Articles/INF24382

Resolution for '2012 r2 issue: 'When will server 2012 r2 be supported?' available: Yes.

The 2012 r2 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 2012 r2 issue yourself by looking for a resolution described in the article. If it is a complex 2012 r2 issue or you are unable to solve the issue, you may contact us by clicking here or by using other 2012 r2 support options.

For more information about resolving issues related to 2012 r2 in Quickbooks/QBO or to get support for the issue 'When will server 2012 r2 be supported?', click the link below: