Compilation of Table 6505 failed because of an I/O error - NAV 2009 R2 RTC

After making some changes to the objects – mostly codeunits, but also some pages, when we compiled the objects (all objects in the DB), restarted NAV Server Service and opened RTC to create transactions – Suddenly RTC started to fail at various steps, giving the following error:

Microsoft Dynamics NAV

Compilation of Table 6505 failed because of an I/O error on the following computer: xxxx. Error details: The process cannot access the file ‘C:\ProgramData\Microsoft\Microsoft Dynamics NAV\60\Server\MicrosoftDynamicsNavServer$NAV\assembly\Record6505_79.dll’ because it is being used by another process.
Page Edit – ‘Name of the Page Object’ must close.


In this example, Table 6505 was the failure point – at other times many other objects – Tables and Codeunits – were also reported.
We have seen some other error messages – related to Objects Metadata and out-of-sync, but this error is new to us.
Client’s Version: NAV 2009 R2 (Build 33750). Only one instance of RTC was open at a time.
Anyone encountered this issue?

Try to delete the particular object record from object metadata table and compile again