In your place I'd do the following:

- deinstall the newly installed version again
- copy all files/subdirectories from the backup into BOINC directory
- install the new version OVER the old one

Installing over the old version will replace the needed files and I'm quite confident that it'll work fine.

:-)= Greybeard

...maybe time solves my problem and my BOINC clear up its mind and start work properly. :))

If not.... My problem will remain and I will not getting new WU's. So I will lost my nice position in my SETI team...

Oooops - that's a new bit of information: Your newly installed BOINC does not download WUs? - Yes I verify that viewing your computers...

Hmmm - that's an other prob, of course.

What does it say in 'messages' tab?

:-)= Greybeard

Well - er - yes, they were right. But then you will have to begin with new WUs and forget the old ones... Copying back WUs from the discarded version to the new one won't work, IMHO.
As this seemed your main concern, I suggested the above.

:-)= Greybeard

In your place I'd do the following:

- deinstall the newly installed version again
- copy all files/subdirectories from the backup into BOINC directory
- install the new version OVER the old one

Installing over the old version will replace the needed files and I'm quite confident that it'll work fine.

:-)= Greybeard

Well, you're welcome, but this information was missing, that's all :)
Just follow Keck's advices ..

Leave it alone. All the suspending, no new work, and junk is most likely why it is not working the way you expect it to. Set your preferences the way you want them maybe do one update to get these preferences from the web site and leave it alone.

Other general advice:
Upgrade BOINC to the 5.2.x version that is currently recommended. There have been many improvements since the version you are running, in fact if I remember correctly that version had a bad bug in it that caused it to be pulled within a few days of release.

CPDN has a fairly long period between checkpoints so I would advise either leaving applications in memory or doing work while the computer is in use. That way you will loose less progress when you use the computer.

Set your queue to the size you really want and leave it alone. This is especially true in the 5.2.x versions, after a few completed workunits the client will really get that much work. I recommend the time you expect a local outage to last divided by the number of projects your are attached to as a maximum queue size. For example if you expect your connection to be down 4 days and you are attached to 2 projects then you should set your queue to no more than 2 days, I personally use 0.3 for my queue. A 10 day queue will likely cause EDF mode for seti and then no seti work will be downloaded until the other project(s) catch up.

To sum things up micromanaging BOINC normally makes whatever you are trying to acomplish harder, decide what settings you want and let BOINC adjust to them.