Case files that have been created within Fluent solution mode can be read into the Fluent GPU Solver. When reading in a Fluent case as outlined in Reading and Writing Case Files, Fluent will attempt to convert any features that are not supported by the GPU solver. Additionally, unsupported features that can not be converted will be disabled by default. After reading in a case, a table similar to the following will be printed in the console that shows any converted or disabled features:

GPU solver defaults are activated for the following unsupported settings (5)
=================================================================================================
Area                   Settings                         From                 To                  
-------------------------------------------------------------------------------------------------
methods                density                          second-order upwind  first-order upwind  
solver                 rhie chow                        distance-weighted    momentum-weighted   
solver                 warped face gradient correction  on                   off                 
solver                 residual scaling                 global               local               
hybrid initialization  averaged turbulent parameters    enabled              disabled         

Although Fluent will attempt to convert or disable most unsupported features after reading a case, there may be some settings that have not been disabled or converted, and are not printed in the console. Upon starting the calculation, if there are any unsupported features still defined, a message similar to the following will be printed in the console:

Following report-files are not valid:
		voltage_vp-rfile:
				Contains following invalid reports:
						voltage_vp:
								Field is not available

Run can not be started until validation issues are resolved.
Deactivate invalid report clients to continue?

You should ensure that the Fluent case file only contains features supported by the GPU solver as outlined in Features Supported by the Fluent GPU Solver, and make any necessary adjustments to the case.