Moving your SQL Server instance’s TempDB files to the D: volume is recommended for performance, as long as the TempDB files fit it the D: that has been allocated, based on your VM size.
When the D: is lost due to deallocation, as expected, the subfolder you created for the TempDB files (if applicable) and the NTFS permissions granting SQL Server permission to the folder are no longer present. SQL Server will be unable to create the TempDB files in the subfolder and will not start. Even if you put the TempDB data and log files in the root of D:, after deallocation, that’s still not a solution, as the NTFS permissions to the root of D: won’t exist. In either case, SQL Server will be unable to create the TempDB files and will not start.
Read on for a few options and William’s thoughts on the relative merits of each.