Thank you, Eric, for your interest and suggestions. My apologies but I should have reported back sooner with an update.
I have two iMacs, one running Mavericks, and this one El C. The Mail settings, servers, ports etc on both iMacs are identical. The Mavericks iMac sends an email using mailhost.xxx without any error. El C iMac gets the error message. Suggesting, therefore, an issue with El C iMac.
Having Googled the error message, suggestions such as deleting and re-establishing the email account were tried without success. I even reloaded El C. Still an error.
Spoke to the ISP today and we double-checked all the settings. All looked OK. In exasperation we decided to try altering the SMTP authentication settings to be 'password' - it was set to None as it has been for the last 8-9 years - and to input the necessary username and password. It worked. No errors. Meanwhile Mavericks iMac is quite happy to send emails using the same SMTP server but with Authentication left at None. Bizarre.
For the record, I ran EtreCheck in OSX in Normal Mode
EtreCheck version: 4.3.4 (4D037)
Report generated: 2018-07-10 17:50:05
Download EtreCheck from https://etrecheck.com
Runtime: 4:51
Performance: Good
Problem: No problem - just checking
Major Issues:
Anything that appears on this list needs immediate attention.
Time Machine backup out-of-date- The last Time Machine backup is over 10 days old.
Obsolete hardware- This machine may be considered obsolete.
Minor Issues:
These issues do not need immediate attention but they may indicate future problems.
Time Machine auto backup disabled- Time Machine auto backups are disabled.
Apps crashing- There have been numerous app crashes.
Clean up- There are orphan files that could be removed.
Unsigned files- There are unsigned software file installed. They appear to be legitimate but should be reviewed.
32-bit Apps- This machine has 32-bits apps that may have problems in the future.
Abnormal shutdown- Your machine shut down abnormally.
Hardware Information:
iMac (2009) - Obsolete!
iMac Model: iMac9,1
1 2.93 GHz Intel Core 2 Duo (Duo) CPU: 2-core
8 GB RAM - At maximum
BANK 0/DIMM0 - 4 GB DDR3 1067 ok
BANK 1/DIMM0 - 4 GB DDR3 1067 ok
Video Information:
NVIDIA GeForce GT 130 - VRAM: 512 MB
iMac 1920 x 1200
Drives:
disk0 - WDC WD6400AAKS-40H2B0 640.14 GB (Mechanical)
Internal SATA 3 Gigabit Serial ATA
disk0s1 - EFI [EFI] 210 MB
disk0s2 - M*******s (Journaled HFS+) 389.15 GB
disk0s3 - Recovery HD [Recovery] 650 MB
disk1 - WD 1.00 TB
External FireWire
disk1s1 - EFI [EFI] 210 MB
disk1s2 - M*****k (Journaled HFS+) 999.83 GB
disk2 - Disk Image 48 MB (Disk Image)
External Disk Image
disk2s1 - A**************************r (HFS+) 48 MB
Mounted Volumes:
disk0s2 - M*******s 389.15 GB (180.72 GB free)
Journaled HFS+
Mount point: /
disk1s2 - M*****k 999.83 GB (793.72 GB free)
Journaled HFS+
Mount point: /Volumes/M*****k
disk2s1 - A**************************r 48 MB (45 MB free)
HFS+
Mount point: /Volumes/A**************************r
Network:
Interface en0: Ethernet
One IPv4 address
Interface fw0: FireWire
Interface en1: Wi-Fi
802.11 a/b/g/n
One IPv4 address
System Software:
OS X El Capitan 10.11.6 (15G22010)
Time since boot: About 8 hours
System Load: 2.61 (1 min ago) 1.72 (5 min ago) 1.52 (15 min ago)
Configuration Files:
/etc/hosts - Count: 1
Security:
| System | Status |
|---|
| Gatekeeper | Mac App Store and identified developers |
| System Integrity Protection | Enabled |
Unsigned Files:
Launchd: /Library/LaunchDaemons/com.prosofteng.DriveGenius.locum.plist
Executable: /Library/PrivilegedHelperTools/com.prosofteng.DriveGenius.locum
Details: Exact match found in the whitelist - probably OK
Launchd: /Library/LaunchDaemons/com.microsoft.office.licensing.helper.plist
Executable: /Library/PrivilegedHelperTools/com.microsoft.office.licensing.helper
Details: Exact match found in the whitelist - probably OK
Launchd: /Library/LaunchAgents/com.oracle.java.Java-Updater.plist
Executable: /Library/Internet Plug-Ins/JavaAppletPlugin.plugin/Contents/Resources/Java Updater.app/Contents/MacOS/Java Updater -bgcheck
Details: Exact match found in the whitelist - probably OK
Launchd: /Library/LaunchDaemons/com.barebones.bbedit.plist
Executable: /Library/PrivilegedHelperTools/com.barebones.bbedit
Details: Exact match found in the whitelist - probably OK
Launchd: ~/Library/LaunchAgents/com.shirtpocket.backupbytime.plist
Executable: /usr/bin/osascript /Users/***/Library/Application Support/SuperDuper!/Scheduled Copies/Backup by Time.scpt
Details: Exact match found in the whitelist - probably OK
Launchd: /Library/LaunchDaemons/com.oracle.java.Helper-Tool.plist
Executable: /Library/Internet Plug-Ins/JavaAppletPlugin.plugin/Contents/Resources/Helper-Tool
Details: Exact match found in the whitelist - probably OK
32-bit Applications:
169 32-bit apps
Kernel Extensions:
/Library/Extensions
[Loaded] LittleSnitch.kext (Objective Development Software GmbH, 3.8.2 - SDK 10.11)
[Not Loaded] usbserial.kext (Jiangsu Qinheng Co., Ltd., 1.1.1 - SDK 10.9)
/System/Library/Extensions
[Not Loaded] ATITVOut.kext (2.6.7 (0001))
System Launch Agents:
| [Not Loaded] | 8 Apple tasks |
| [Loaded] | 151 Apple tasks |
| [Running] | 81 Apple tasks |
System Launch Daemons:
| [Not Loaded] | 47 Apple tasks |
| [Loaded] | 153 Apple tasks |
| [Running] | 91 Apple tasks |
| [Other] | One Apple task |
Launch Agents:
| [Running] | at.obdev.LittleSnitchUIAgent.plist (Objective Development Software GmbH - installed 2018-03-31) |
| [Running] | com.micromat.TechToolProAgent.plist (Micromat, Inc. - installed 2016-09-03) |
| [Running] | com.micromat.CheckmateAgent.plist (? c2cac71 - installed 2018-05-04) |
| [Loaded] | com.oracle.java.Java-Updater.plist (? f7f7b8ab - installed 2018-03-28) |
Launch Daemons:
| [Running] | com.bombich.ccchelper.plist (? df62b69b - installed 2017-01-26) |
| [Running] | at.obdev.littlesnitchd.plist (Objective Development Software GmbH - installed 2018-03-31) |
| [Loaded] | com.malwarebytes.MBAMHelperTool.plist (Malwarebytes Corporation - installed 2015-11-23) |
| [Loaded] | com.prosofteng.DriveGenius.locum.plist (? d39b1525 - installed 2014-02-10) |
| [Running] | com.micromat.popHelper.plist (Micromat, Inc. - installed 2016-06-26) |
| [Loaded] | com.apple.installer.osmessagetracing.plist (Apple - installed 2018-06-29) |
| [Running] | com.micromat.TechToolProDaemon.plist (Micromat, Inc. - installed 2016-09-03) |
| [Loaded] | com.adobe.fpsaud.plist (Adobe Systems, Inc. - installed 2018-06-25) |
| [Loaded] | com.microsoft.office.licensing.helper.plist (? 6d8cb30e - installed 2010-08-25) |
| [Loaded] | com.oracle.java.Helper-Tool.plist (? e3fefdd2 - installed 2018-03-28) |
| [Running] | com.micromat.CheckmateIdleDaemon.plist (Micromat, Inc. - installed 2018-05-04) |
| [Loaded] | com.micromat.CheckmateWorkerDaemon.plist (? 9796698e - installed 2018-05-04) |
| [Loaded] | com.charlessoft.pacifist.helper.plist (? af18ad2 - installed 2014-10-20) |
| [Not Loaded] | com.barebones.bbedit.plist (? 76c927a0 - installed 2010-06-23) |
| [Loaded] | com.rogueamoeba.instanton-agent.plist (? c3a85319 - installed 2016-02-16) |
User Launch Agents:
| [Other] | com.google.keystone.agent.plist (? 0 - installed 2017-07-12) |
| [Loaded] | com.dropbox.DropboxMacUpdate.agent.plist (Dropbox, Inc. - installed 2018-04-13) |
| [Loaded] | com.shirtpocket.backupbytime.plist (? 0 - installed 2018-07-08) |
| [Not Loaded] | com.hp.devicemonitor.plist (HP Inc. - installed 2017-10-25) |
| [Running] | com.c-command.SpamSieve.LaunchAgent.plist (C-Command Software, LLC - installed 2018-04-30) |
| [Loaded] | com.adobe.ARM.***.plist (Adobe Systems, Inc. - installed 2017-11-01) |
User Login Items:
iTunesHelper Application (Apple - installed 2018-07-10)
(/Applications/iTunes.app/Contents/MacOS/iTunesHelper.app)
SMARTReporter Application (? - installed 2016-03-14)
(/Applications/SMARTReporter.app)
TextExpander Application (?)
(/Users/***/Documents/Software)
Rogue Amoeba Schedule Helper Application (? - installed 2014-10-27)
(/Library/Application Support/Audio Hijack Pro/Rogue Amoeba Schedule Helper.app)
CCC User Agent Application (? - installed 2017-01-12)
(/Applications/Carbon Copy Cloner-2.app/Contents/Library/LoginItems/CCC User Agent.app)
iSkysoft Helper Compact Application (? - installed 2016-10-25)
(/Users/***/Library/Application Support/Helper/iSkysoft Helper Compact.app)
Internet Plug-ins:
DirectorShockwave: 11.5.1r601 (installed 2009-09-03)
WacomNetscape: 1.1.1-1 (installed 2012-01-20)
Default Browser: 601 (installed 2017-08-09)
Flip4Mac WMV Plugin: 3.3.7.3 (installed 2016-07-28)
NP_2020Player_WEB: 5.0.94.0 (installed 2011-10-26)
RealPlayer Plugin: (installed 2014-04-21)
AdobePDFViewerNPAPI: 11.0.23 (installed 2017-11-15)
FlashPlayer-10.6: 30.0.0.134 (installed 2018-07-10)
NP_2020Player_IS: 7.2.0.53 (installed 2017-06-26)
Silverlight: 5.1.41212.0 (installed 2016-07-04)
QuickTime Plugin: 7.7.3 (installed 2018-07-10)
Flash Player: 30.0.0.134 (installed 2018-07-10)
iPhotoPhotocast: 7.0 (installed 2010-04-01)
SharePointBrowserPlugin: 14.0.0 (installed 2010-08-25)
AdobePDFViewer: 11.0.23 (installed 2017-11-15)
WacomTabletPlugin: WacomTabletPlugin 2.0.0.4 (installed 2012-01-20)
GoogleOneClickPluginDeluxe: 1.0 (installed 2009-09-03)
JavaAppletPlugin: Java 8 Update 171 build 11 (installed 2018-05-11)
Safari Extensions:
| DuckDuckGo.safariextz - DuckDuckGo - http://duckduckgo.com (installed 2017-02-08) |
| AllMyTube.safariextz - Wondershare Software Co. - http://www.wondershare.com (installed 2012-04-18) |
| Blur.safariextz - Abine, the online privacy company. - https://www.abine.com(installed 2017-01-07) |
| iMedia Converter Deluxe .safariextz - iSkysoft Studio - http://www.iskysoft.com(installed 2015-07-30) |
| Quickstyle.safariextz - Canisbos Computing - http://canisbos.com/(installed 2016-09-21) |
| Ghostery.safariextz - GHOSTERY, Inc. - https://www.ghostery.com/ (installed 2017-02-14) |
| AdBlock.safariextz - BetaFish, Inc. - https://getadblock.com (installed 2017-11-08) |
| Google Analytics Opt-out Browser Add-on.safariextz - Google, Inc. - http://tools.google.com/dlpage/gaoptout(installed 2014-10-11) |
3rd Party Preference Panes:
ATI Displays (installed 2009-09-03)
EarthDesk (installed 2008-04-28)
Flash Player (installed 2018-06-25)
Flip4Mac WMV (installed 2016-07-28)
FUSE for OS X (OSXFUSE) (installed 2012-07-30)
Java (installed 2018-05-11)
Squeezebox (installed 2016-03-14)
MacFUSE (Tuxera) (installed 2013-09-08)
Perian (installed 2011-07-23)
TechTool Protection (installed 2016-09-03)
Time Machine:
Skip System Files: No
Mobile backups: No
Auto backup: No
Volumes being backed up:
M*******s: Disk size: 389.15 GB - Disk used: 208.42 GB
Destinations:
D**a [Network] (Last used)
Total size: 997.71 GB
Total number of backups: 87
Oldest backup: 2016-04-21 00:00:00
Last backup: 2017-03-29 08:25:06
Top Processes by CPU:
| Process (count) | Source | % of CPU | Location |
| system_profiler (2) | Apple | 62 |
| WindowServer | Apple | 15 |
| systemstatsd | Apple | 9 |
| CheckmateAgent | ? | 7 | /Library/Checkmate/CheckmateAgent.app |
| ocspd | Apple | 4 |
Top Processes by Memory:
| Process (count) | Source | RAM usage | Location |
| kernel_task | Apple | 742 MB |
| com.apple.WebKit.WebContent (3) | Apple | 593 MB |
| Safari | Apple | 578 MB |
| softwareupdated | Apple | 456 MB |
| mds_stores | Apple | 280 MB |
Top Processes by Energy Use:
| Process (count) | Source | Energy (0-100) | Location |
| CheckmateAgent | ? | 4 | /Library/Checkmate/CheckmateAgent.app |
| WindowServer | Apple | 2 |
| Activity Monitor | Apple | 1 |
| com.apple.WebKit.Networking | Apple | 1 |
| diskarbitrationd | Apple | 1 |
Virtual Memory Information:
| Available RAM | 2.45 GB |
| Free RAM | 18 MB |
| Used RAM | 5.55 GB |
| Cached files | 2.43 GB |
| Swap Used | 0 B |
Software Installs (past 30 days):
| Name | Version | Install Date |
| MRTConfigData | 1.35 | 2018-06-20 |
| Bandwidth+ | 1.11 | 2018-06-21 |
| Gatekeeper Configuration Data | 146 | 2018-07-04 |
| SuperDuper! | 3.1.7 | 2018-07-06 |
| Security Update 2018-004 | 10.11.6 | 2018-07-10 |
| iTunes | 12.8 | 2018-07-10 |
| Safari | 11.1.2 | 2018-07-10 |
| Adobe Flash Player | 30.0.0.134 | 2018-07-10 |
Clean up:
~/Library/LaunchAgents/com.google.keystone.agent.plist
/Users/***/Library/Google/GoogleSoftwareUpdate/GoogleSoftwareUpdate.bundle/Conte nts/Resources/GoogleSoftwareUpdateAgent.app/Contents/MacOS/GoogleSoftwareUpdateA gent
Executable not found
Diagnostics Information (past 7 days):
2018-07-10 09:10:55 Last Shutdown Cause: 0 - Power loss
2018-07-09 21:47:52 com.apple.WebKit.Databases Crash
/System/Library/Frameworks/WebKit.framework/Versions/A/XPCServices/com.apple.Web Kit.Databases.xpc/Contents/MacOS/com.apple.WebKit.Databases
2018-07-09 19:13:49 mdworker Crash
/System/Library/Frameworks/CoreServices.framework/Versions/A/Frameworks/Metadata .framework/Versions/A/Support/mdworker
import fstype:hfs fsflag:480D100 flags:410000025E diag:0 isXCode:0 uti:com.apple.application-bundle plugin:/Library/Spotlight/Application.mdimporter - find suspect file using: sudo mdutil -t 6395614 libcoreservices: _dirhelper: 400: mkdir: path=/var/folders/zz/zyxvpxvq6csfxvn_n00000b400002s/C/ modes[2]=0700: Operation not permitted |
2018-07-05 10:56:03 quicklookd.app Crash
/System/Library/Frameworks/QuickLook.framework/Versions/A/Resources/quicklookd.a pp
objc_msgSend() selector name: objectForKey: qlmanage --diag |
2018-07-04 08:30:55 Preview.app Crash
/Applications/Preview.app
objc_msgSend() selector name: _progressPanelWasCancelled:contextInfo: Performing @selector(cancelButtonPressed:) from sender NSButton 0x7ff4d7a5c9c0 |
2018-07-04 08:25:54 MassStorageCamera.app Crash (3 times)
/System/Library/Image Capture/Devices/MassStorageCamera.app
abort() called *** error for object 0x7fde20532638: incorrect checksum for freed object - object was probably modified after being freed. |
End of report
