WARNING: Your ClamAV installation is OUTDATED!
WARNING: Local version: 0.101.2 Recommended version: 0.103.5
DON'T PANIC! Read https://www.clamav.net/documents/upgrading-clamav
main.cld is up to date (version: 62, sigs: 6647427, f-level: 90, builder: sigmgr)
WARNING: getpatch: Can't download daily-26440.cdiff from database.clamav.net
WARNING: getpatch: Can't download daily-26440.cdiff from database.clamav.net
ERROR: getpatch: Can't download daily-26440.cdiff from database.clamav.net
WARNING: Incremental update failed, trying to download daily.cvd
ERROR: Can't download daily.cvd from database.clamav.net
Giving up on database.clamav.net...
Update failed. Your network may be down or none of the mirrors listed in /etc/freshclam.conf is working. Check https://www.clamav.net/documents/official-mirror-faq for possible reasons.

Solution:

yum -y --enablerepo=epel update clam*
freshclam

Test ClamAV

Send an email with content

X5O!P%@AP[4\PZX54(P^)7CC)7}$EICAR-STANDARD-ANTIVIRUS-TEST-FILE!$H+H*

If ClamAV works you will see the following in the log: /var/log/maillog

Dec 27 07:22:42 cwp1 clamd[17958]: /var/spool/amavisd/tmp/amavis-20211227T071305-18132-Ocyoo8yY/parts/p001: {HEX}EICAR.TEST.3.UNOFFICIAL FOUND

Dec 27 07:22:42 cwp1 amavis[18132]: (18132-02) Blocked INFECTED ({HEX}EICAR.TEST.3.UNOFFICIAL) {DiscardedOpenRelay,Quarantined}, [209.85.216.47]:46925 [209.85.216.47]  -> , Queue-ID: 9762E703FD2, Message-ID: , mail_id: TKHZnGx2Bs7T, Hits: -, size: 3868, dkim_sd=20210112:gmail.com, 111 ms

Dec 27 07:22:42 cwp1 postfix/smtp[12663]: 9762E703FD2: to=, relay=127.0.0.1[127.0.0.1]:10024, delay=0.34, delays=0.21/0.02/0/0.11, dsn=2.7.0, status=sent (250 2.7.0 Ok, discarded, id=18132-02 - INFECTED: {HEX}EICAR.TEST.3.UNOFFICIAL)

Test SpamAssassin

Send an email with content:

XJS*C4JDBQADN1.NSBN3*2IDNEN*GTUBE-STANDARD-ANTI-UBE-TEST-EMAIL*C.34X

If SpamAssassin works you will see the following in the log: /var/log/maillog

Dec 27 07:25:37 cwp1 amavis[18133]: (18133-02) Blocked SPAM {DiscardedOpenRelay,Quarantined}, [209.85.215.174]:37637 [209.85.215.174]  -> , Queue-ID: 59C16703FD2, Message-ID: , mail_id: vES-jRB7LKPt, Hits: 999.904, size: 3903, dkim_sd=20210112:gmail.com, 579 ms

Starting from the CWP version 0.9.6+ you have a new awesome Postfix Mail Server Manager (Re-Builder)
With a single click you can select additional Mail Server options and ReBuild your mail server according to your needs.

Location in the CWP.admin area
Left Menu --> Email --> Postfix Manager

Options
- AntiSpam and AntiVirus Protection (Spamassassin and ClamAV are scanning all your incoming emails, this requires server with min. 1Gb of RAM).
- rDNS check (Drop all emails if no rDNS/PTR)
- Reject Unknown Hostname (Reject unless the hostname has valid DNS record, IGNORE as you could be blocked also)

AntiSpam and AntiVirus
It's possible that ClamAV Antivirus will work with 512MB RAM server but its recommended to have at least 1GB+ RAM.