I have modified a Maintenance plan on SQL Server 2008 using SSMS 2014, particularly Reorganize index task - I have added another two databases for this task.
When I wanted to check if the T-SQL is OK, the View T-SQL button shows the error:
unknown property IsMemoryOptimized
Could (should?) that be fixed somehow?
Converting comment to answer so as to close this question:
Most probable reason that error has been witnessed in SQL server 2014, could be you are not updated to the latest cumulative updates.
unknown property IsMemoryOptimized
has been reported as bug, may not be somewhat similar to you're situation, but CU has been suggested.
However, for now, please try to make the changes using the SQL server 2008/R2 and see if that works.
