I was contacted by a "good source", and was told how to fix this issue.
The procedure is as follows:
1. It requires an Aastra DT390 or DT690 DECT handset and an advanced charger (with the Aastra number BML351061/1 R1A) with USB connection to your PC.
2. WinPDM program must be running on your PC.
3. The following software versions be used:
a. Win PDM must be version 3.1.8.
b. DT390/690 be in version 2.8.19.
c. The charger s/w should be in version 1.3.8.
To install the phone book use the worksheet (Excel) "Company Phone Book". This document should be completed, saved, converted (to "cpb" file format) and loaded into the phone.
After the worksheet is completed, press the button "Create Phone Book" and the file format is changed to "CPB" format.
In Win PDM find the DECT handset to which the phone book should be loaded, and do a "right-mouse" click on it.
Hereby the option: "Load phone book" appears, click on it and in a few seconds the phone book is loaded into the DECT handset.
Please note that the s/w of all device should minimum be the mentioned levels.
///doktor