• I don't know how far you want to pursue this, but here are some thoughts I have had in no particular order.

      [*]There is a handy dandy free troubleshooting app Etrecheck that is useful at identifying potentially problematic extensions, plug-ins, etc. You might try running it to see if anything pops up. I know it helped me identify a couple of out of date kernel extensions that were causing me some issues. I ran etrecheck and this is the result. It is Greek to me. Problem description:
      My Mail has been coming in as code in my Yahoo email account instead of HTML from commercial websites such as Amazon, my insurance company, the post office and others. It comes in fine in Thunderbird. It also sometimes happens at the Yahoo Mail Website, not just the Mail program.

      EtreCheck version: 2.2 (132)
      Report generated 5/4/15, 10:13 PM
      Download EtreCheck from http://etresoft.com/etrecheck

      Click the [Click for support] links for help with non-Apple products.
      Click the [Click for details] links for more information about that line.

      Hardware Information: ℹ️
      MacBook Pro (13-inch, Mid 2012) (Technical Specifications)
      MacBook Pro - model: MacBookPro9,2
      1 2.5 GHz Intel Core i5 CPU: 2-core
      4 GB RAM Upgradeable
      BANK 0/DIMM0
      2 GB DDR3 1600 MHz ok
      BANK 1/DIMM0
      2 GB DDR3 1600 MHz ok
      Bluetooth: Good - Handoff/Airdrop2 supported
      Wireless: en1: 802.11 a/b/g/n
      Battery: Health = Normal - Cycle count = 224 - SN = 9G21809N1D3MB

      Video Information: ℹ️
      Intel HD Graphics 4000
      Color LCD 1280 x 800

      System Software: ℹ️
      OS X 10.9.4 (13E28) - Time since boot: 14:11:42

      Disk Information: ℹ️
      APPLE HDD HTS547550A9E384 disk0 : (500.11 GB)
      EFI (disk0s1) <not mounted> : 210 MB
      Macintosh HD (disk0s2) / : 499.25 GB (458.52 GB free)
      Recovery HD (disk0s3) <not mounted> [Recovery]: 650 MB

      HL-DT-ST DVDRW GS31N

      USB Information: ℹ️
      Apple Inc. FaceTime HD Camera (Built-in)
      Apple Inc. BRCM20702 Hub
      Apple Inc. Bluetooth USB Host Controller
      Apple Inc. Apple Internal Keyboard / Trackpad
      Apple Computer, Inc. IR Receiver

      Thunderbolt Information: ℹ️
      Apple Inc. thunderbolt_bus

      Gatekeeper: ℹ️
      Anywhere

      Launch Daemons: ℹ️
      [loaded] com.adobe.fpsaud.plist [Click for support]

      User Launch Agents: ℹ️
      [loaded] com.shirtpocket.backupbytime.plist [Click for support]
      [loaded] com.shirtpocket.backuponmount-login.plist [Click for support]
      [loaded] com.shirtpocket.backuponmount.plist [Click for support]

      User Login Items: ℹ️
      iTunesHelper Application Hidden (/Applications/iTunes.app/Contents/MacOS/iTunesHelper.app)
      EtreFeed Application Hidden (/Applications/Etrefeed/EtreFeed.app)
      Journler Application (/Users/[redacted]/Downloads/Journler.app)

      Internet Plug-ins: ℹ️
      FlashPlayer-10.6: Version: 17.0.0.169 - SDK 10.6 [Click for support]
      QuickTime Plugin: Version: 7.7.3
      Flash Player: Version: 17.0.0.169 - SDK 10.6 [Click for support]
      Default Browser: Version: 537 - SDK 10.9
      GarminGpsControl: Version: 4.1.0.0 Release - SDK 10.7 [Click for support]
      googletalkbrowserplugin: Version: 5.40.2.0 - SDK 10.8 [Click for support]
      JavaAppletPlugin: Version: 14.8.0 - SDK 10.9 Check version

      User internet Plug-ins: ℹ️
      CitrixOnlineWebDeploymentPlugin: Version: 1.0.105 [Click for support]

      Safari Extensions: ℹ️
      Ghostery
      Subscribe To Feed
      Disconnect
      Cuss Off
      ClickToFlash
      ClickToPlugin
      FastestTube
      AdBlock
      Adblock Plus

      3rd Party Preference Panes: ℹ️
      RCDefaultApp
      Flash Player [Click for support]
      Logitech Control Center [Click for support]
      Perian [Click for support]

      Time Machine: ℹ️
      Time Machine not configured!

      Top Processes by CPU: ℹ️
      10% WindowServer
      9% thunderbird
      4% fontd
      0% mdworker(3)
      0% aosnotifyd

      Top Processes by Memory: ℹ️
      565 MB com.apple.WebKit.WebContent(7)
      473 MB kernel_task
      365 MB Safari
      217 MB thunderbird
      123 MB com.apple.IconServicesAgent

      Virtual Memory Information: ℹ️
      51 MB Free RAM
      3.94 GB Used RAM
      0 B Swap Used

      Diagnostics Information: ℹ️
      May 4, 2015, 12:24:01 PM /Users/[redacted]/Library/Logs/DiagnosticReports/Mail_2015-05-04-122401_[redacted].crash
      May 4, 2015, 08:00:35 AM Self test - passed





      [ I was recently having some inexplicable problems on one of my Macs that at the suggestion of the Genius Desk at the local Apple Store they were cured by flushing all — and I do mean ALL — of the various cache files in the entire system. That involved going to /System/Library/Caches, /Library/Caches, and ~/Library/Caches and deleting all the files and folders in each of those locations. It might slow things down a bit until all the caches are rebuilt, but who knows it might, just might solve your issue. (It is almost scary how many grow back so rapidly when you do that.) [*]

      [/color]I looked at those cache files (didn't know where to look for the system cache files), and it scared me. I was afraid I would screw something up by deleting them all. I do use OnyX to delete cache files, though.

      [color:#000000][color:#660000
      ]Escalate the issue by gathering up a couple of sample emails (raw text versions so non=printing ASCII would show up in a Hex editor), a System Report and a careful description of that problem and what you have done to troubleshoot it and contact AppleCare and if necessary be prepared to request the issue to be escalated. The more data you have available the better. Personally I would put all the files in a folder on iCloud so you can share the data with them rather than attempting to email all of that because the files will get LARGE. [*]
      [/color]
      [/color]I did all that above with the Apple Mail Tech. We went into it extensively and made copies of stuff and sent it over to Engineering. I can't remember what we did exactly, but he was in my computer helping me get all the info together along with pics of my emails.

      In the interim, if you are not too thrilled with Thunderbird you might try Airmail 2. It is available through the App Store. They no longer offer a free trial of the released version, but you can get a free download of the 2.1 beta which I am using and it is very stable. I have come to prefer it to Mail — much to my surprise. [*]

      [color:#FF0000]I may try the beta Airmail. I really don't care for Thunderbird. The fonts are small and I can't enlarge them even with an add-on plugin. Also, can't get used to their interface.



      If all else fails there is always the nuclear option.
      1. Back up everything, cloning is recommended. Gather up any current application install DVDs installation keys etc. ????? Make a list of all your download installs (if they are from the App Store it will remember for you.) Be sure your Keychain, Calendars, Contacts, Photos, Tunes, etc. are all in iCloud.
      2. Sorry, I don't like the Cloud. Too easy to hack.[/color]


        Boot from the Recovery Drive (either option boot of boot holding down ⌘R) and erase the Hard Drive then Install Mavericks.
      3. Go through the setup routine, but do NOT restore from either the Time Machine or clone backups.
      4. Reconnect to iCloud to restore all your passwords and other settings (you might hold off on Mail and set that up completely from scratch — just in case).
      5. Copy any data files not in iCloud from the clone by drag and drop or from the latest Time Machine backup.
      6. Re-install your non-App Store applications — ONE AT A TIME and carefully testing Mail after each.
      7. Re-install any kernel extensions, plug-ins, anti-malware applications — ONE AT A TIME and carefully testing Mail after each.
      8. Don't re-install any application, kernel extension, plug-in, etc. UNLESS YOU REALLY NEED IT.
      9. I Hope it does not come to this as it is a pain in the nether regions of the anatomy and very time consuming. Even worse it does not guarantee a fix.
  • [/quote] [/color][color:#CC0000]Wow, that IS a lot of work. I have a SuperDuper backup already. I guess that's a clone backup? Gosh, I hope I don't have to go this far. Too scary and complicated for me. I do appreciate all the instructions, though. And maybe one day they will all make sense to me.

    [color:#33FF33]Sorry about the messy color changes.


    Rita[/color]


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