LHC@home

Some Atlas-jobs on two of my PCs didn't start their work (comp. 10569623 and 10382024). They run endless, doing nothing.
I see two types of errors in the log files (stderr.txt or VBox.log):

1. Samples like this:
2020-01-18 06:57:59 (9840): Guest Log: Checking CVMFS...
2020-01-18 06:58:00 (9840): Guest Log: Failed to check CVMFS, check output from cvmfs_config probe:
2020-01-18 06:58:01 (9840): Guest Log: Probing /cvmfs/atlas.cern.ch... Failed!
2020-01-18 06:58:01 (9840): Guest Log: Probing /cvmfs/atlas-condb.cern.ch... Failed!
2020-01-18 06:58:01 (9840): Guest Log: Probing /cvmfs/grid.cern.ch... Failed!
2020-01-18 06:58:11 (9840): Guest Log: VBoxService 5.2.32 r132073 (verbosity: 0) linux.amd64 (Jul 12 2019 10:32:28) release log
2020-01-18 06:58:11 (9840): Guest Log: 00:00:00.000172 main Log opened 2020-01-18T06:58:09.566143000Z
2020-01-18 06:58:11 (9840): Guest Log: 00:00:00.000279 main OS Product: Linux
2020-01-18 06:58:11 (9840): Guest Log: 00:00:00.000316 main OS Release: 3.10.0-957.27.2.el7.x86_64
…
and never this lines:

00:00:30.325812 VMMDev: Guest Log: CVMFS is ok

The tasks probably have not enougth memory:

00:00:00.435418 Host RAM: 16294MB (15.9GB) total, 4069MB (3.9GB) available
00:00:00.435420 Executable: C:\Program Files\Oracle\VirtualBox\VBoxHeadless.exe
00:00:00.435421 Process ID: 6892
or
00:00:00.936929 Host RAM: 16294MB (15.9GB) total, 3608MB (3.5GB) available
00:00:00.936931 Executable: C:\Program Files\Oracle\VirtualBox\VBoxHeadless.exe
00:00:00.936931 Process ID: 15204

2. A second type, with enougth memory (8.2GB) is here:

00:00:32.202025 VMMDev: Guest Log: Checking CVMFS...
00:00:39.401098 VMMDev: Guest Log: VBoxService 5.2.32 r132073 (verbosity: 0) linux.amd64 (Jul 12 2019 10:32:28) release log
00:00:39.401126 VMMDev: Guest Log: 00:00:00.000235 main Log opened 2020-01-20T13:43:51.889924000Z
00:00:39.401187 VMMDev: Guest Log: 00:00:00.000347 main OS Product: Linux
00:00:39.401221 VMMDev: Guest Log: 00:00:00.000383 main OS Release: 3.10.0-957.27.2.el7.x86_64
00:00:39.401350 VMMDev: Guest Log: 00:00:00.000510 main OS Version: #1 SMP Mon Jul 29 17:46:05 UTC 2019
00:00:39.401388 VMMDev: Guest Log: 00:00:00.000550 main Executable: /opt/VBoxGuestAdditions-5.2.32/sbin/VBoxService
00:00:39.401399 VMMDev: Guest Log: 00:00:00.000550 main Process ID: 1540
00:00:39.401407 VMMDev: Guest Log: 00:00:00.000551 main Package type: LINUX_64BITS_GENERIC
00:00:39.402401 VMMDev: Guest Log: 00:00:00.001548 main 5.2.32 r132073 started. Verbose level = 0
00:00:39.403521 Guest Control: GUEST_MSG_REPORT_FEATURES: 0x1, 0x8000000000000000
00:00:49.405064 VMMDev: Guest Log: 00:00:10.004191 timesync vgsvcTimeSyncWorker: Radical guest time change: -3 607 552 511 000ns (GuestNow=1 579 524 224 340 661 000 ns GuestLast=1 579 527 831 893 172 000 ns fSetTimeLastLoop=true )
00:10:10.286013 Display::i_handleDisplayResize: uScreenId=0 pvVRAM=000000000afc0000 w=800 h=600 bpp=0 cbLine=0xC80 flags=0x5 origin=0,0
05:36:04.375518 Changing the VM state from 'RUNNING' to 'SUSPENDING'
05:36:04.418269 PDMR3Suspend: 42 532 011 ns run time
05:36:04.418314 Changing the VM state from 'SUSPENDING' to 'SUSPENDED'
------------------------------------------------------------------------------------------------------

I checked according to the checklist:
My AntiVirus ignores the BOINC_Data-Directory. I reinstalled Boinc and different versions of VM.
What else could help here.

Older results (last 30 days) with errors are:
https://lhcathome.cern.ch/lhcathome/result.php?resultid=257971613
https://lhcathome.cern.ch/lhcathome/result.php?resultid=257349880
https://lhcathome.cern.ch/lhcathome/result.php?resultid=257189343
https://lhcathome.cern.ch/lhcathome/result.php?resultid=256751957
https://lhcathome.cern.ch/lhcathome/result.php?resultid=258528225
https://lhcathome.cern.ch/lhcathome/result.php?resultid=258573637
https://lhcathome.cern.ch/lhcathome/result.php?resultid=259458789