After several LHC/CMS tasks had crashed, they were shown in the BOINC Manager with "computation error", and I was not able to remove these tasks from the Manager (however, I could remove them in the Oracle Virtual Box Manager). As long as this was the case, no new tasks could be downloaded; no way to get these entries removed from the BOINC Manager.
So I decided to reset the LHC project, which was successful in a way that the crashed tasks did no longer show up in the BOINC Manager.
However, if I click on "update" for getting new tasks, the BOINC Manager in the "status" column shows "communication deferred 24 hours, and this is now counting downwards every minute, for the next 24 hours :-( In other words, I will have to wait for a full day in order to get new tasks downloaded.
What I also tried about 1 hour later was to restart the BOINC client (as well as the BOINC Manager) - and while before doing this, the remaining time was shown as some 23 hours, after restart it had jumped back to 24 hours and is now again counting down from there.
What's going wrong? Any ideas how to solve the problem ?

I think this is an LHC issue and that when tasks are aborted, they impose a 24 hour back off till you can get more tasks and there is nothing you can do but wait. Have you tried the LHC forums? There should be someone there who can answer this.

In reply to Dave's message of 23 May 2025:

I think this is an LHC issue and that when tasks are aborted, they impose a 24 hour back off till you can get more tasks and there is nothing you can do but wait. Have you tried the LHC forums? There should be someone there who can answer this.

Yes, someone very knowledgeable from there gave me the advice to restart the Boinc client. As mentioned above, this did not help though.
Further, I don't think the problem is related to LHC specifically. There have been many cases that I aborted tasks, over the years (for one reason or the other), but never ever the Boinc Manager bahaved the way it does now. Also, if there was indeed this 24 hour limit, why does the counter still jump back to 24 hours each time I push the "update" button? I am sure that the problem is related to BOINC. And I am even not sure what will happen after the 24 hours are gone. Maybe it then again jumps back to 24 hours the moment I push "update".

Well, I can wait till tomorrow, no problem. If the situation then is still the same, I guess all I can do is to uninstall and reinstall BOINC.

So, what I did now was:
The counter showed 21:58 hours, I closed the Boinc Manager and the Boinc client and ran the Boinc "repair" installation.
Even this did now help, the counter jumped back to 24 hours.
It's a conondrum :-(

Go to your account and select Computers on this account, View.
Click on detail. Then Application details, click on Show.
For each application, there will be a Max Tasks per day value. Generally, for each errored Task, that value is reduced by one, till it gets down to 1.
If before it reaches 1, no Valid Tasks are returned, then you won't be able to get any more Tasks for 24 hours. Once that time passes, you will get one Task. Once it completes and Validates, then you will be able to get 2 Tasks. Once they Validate, then 4 Tasks. etc. Any further errors, it will be reduced by one for each error again.


If you look in your Event log there should be a message along the lines of "You have reached your daily quota of Tasks." I don't recall it resulting in a 24 hour back off, but that can be set by the project.
(even without that, the increasing backoffs for failed Scheduler contacts are somewhat excessive- it doesn't take many to reach 24hr backoffs. However- clicking on Update for the project generally resets the backoff's to the project default (ie 30sec, 1min, 5min etc depending on the project). Exiting and restarting BOINC does the same thing. If the initial contact with the project results in a 24hr backoff- it sounds very much like a project setting).

---

Grant
Darwin NT.

Problem solved: by coincidence, I noticed that the IP address of the notebook was changed (no idea how come, because on the router I have set it as fixed). And for this reason, the squid proxy did not allow the connection to LHC. So I added the new IP address to the hosts list in the squid.config of the proxy, and now it works :-)