When an add-in does not communicate with the host for 5 minutes or longer, then attempts to communicate again the error "xxx.rem has been disconnected or does not exist at the server" occurs.  This happens both during debugging and at run time and is due to unwanted garbage collection.

This is a bug outside of VSTA and will be fixed in the .Net 3.5 SP1.

Steps to repro:

1)     Open ShapeAppMacroRecordingCSharp

2)     Record a macro

3)     Get a cup of coffee (leave the host application idle for longer than 5 minutes)

4)     Run a macro

5)     Error "xxx.rem has been disconnected or does not exist at the server" occurs

Until SP1 for .Net 3.5 is released, this problem can be avoided by adding a method to add-ins that will periodically call into the host application (we suggest a “do nothing” method, for example check a property value).  This regular communication prevents the “accidental garbage collection” that is taking place and disconnecting the add-in from the host.