X1 and Lotus Noted missing e-mail

Hi there.
I'm using X1 Professional Client Version 6.7.4 (Build 4054ff) (Created: Wed Sep 26 16:13:42 PDT 2012) on IBM Lotus Notes 8.5, Release 8.5.2, Revision 20100811.1131 (Release 8.5.2), Standard Configuration and windows 7, 64 bit Enterprise.

I use X1 to search the Domino server mail as well as local archived e-mail.

It works well, however every now and then an e-mail is "missing"....
If I search for it, I find it in X1, it shows the content of the e-mail, date, time, etc. however If I double click on it to try and open it on Lotus Notes, I get an error in Lotus Notes: "Unable to find path to server....." As far as I know the e-mail should be in the local achivies.

I tired to re-index X1 several times, but it still shows the file when I search for it and when I try and open it (by double clicking on it), it gives the same error.

So it looks like the X1 Index and Search does find the e-mail, but why then can Lotus Notes not?
Is there a way how I can see in which specific archive that e-mail is located?

Thank you for EXCELLENT software!

Piet

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