Hi Bill, The sendmail config parameter is what i was looking for.We have 2 ways to send mail.The sendmail value or the smtphost etc. As you have sendmail configured you will need to work out what's happened to the sendmail setup on your system.  I don't know if you are really us8ng sendmail or one of the other mailers like ssmtp. ls - la /usr/sbin/sendmail Will help identify that. Drop in to the room at https://riot.im/app/#/room/#ledgersmb:matrix.org and we can discuss in real time which will make it easier to help out on this one. Regards David G Sent from my Samsung Mobile on the Telstra Mobile Network -------- Original message --------From: bill Ott <billott@theotts.org> Date: 2/7/18 18:33 (GMT+08:00) To: David Godfrey <lsmbdev@sbts.com.au> Cc: users@lists.ledgersmb.org Subject: Re: [ledgersmb-users] Broken mail Thanks, David.  There is really nothing set in the LSMB config other than to point to the mailer. [mail] ### How to send mail.  The sendmail command is used unless smtphost is set. sendmail   = /usr/sbin/sendmail # smtphost = 127.0.0.1 # smtptimeout = 60 # backup_email_from = backups@lsmb_hosting.com I am not convinced that the failure has anything to do with the mailing. The only proxy server I run is the connection between starman and apache, if I understand that correctly. Regards, Bill Ott Home: 919-363-0031 Cell: 919-434-7589 Email: Mailto:billott@theotts.org Website: http://www.theotts.org Profile: http://www.linkedin.com/in/wbott On 07/01/2018 11:49 AM, David Godfrey wrote: Hi Bill, It might help if you can tell us how you configured your mail server settings. This is normally done in ledgersmb.conf.  Please obscure any usernames and passwords in your reply.  Regards  David G Sent from my Samsung Mobile on the Telstra Mobile Network -------- Original message -------- From: bill Ott <billott@theotts.org> Date: 1/7/18 22:28 (GMT+08:00) To: users@lists.ledgersmb.org Subject: [ledgersmb-users] Broken mail I am currently running 1.5.12 and have been since it's release. On 25 June 2018 using the recurring transactions, invoices were mailed to ~20 tenants, all successfully sent and received (I am copied on them, so I know). Today 1 July, I successfully posted a number of checks (cash->receipts), after which I attempted to send "paid invoice emails". I received the following error message. "Proxy Error The proxy server received an invalid response from an upstream server. The proxy server could not handle the request POST /ledgersmb/is.pl. Reason: Error reading from remote server" From the access_log: 192.168.0.240 - - [01/Jul/2018:09:57:10 -0400] "POST /ledgersmb/is.pl HTTP/1.1" 502 410 "https://www.theotts.org/ledgersmb/login.pl?action=login&company=SalemStreetN" "Mozilla/5.0 (X11; Fedora; Linux x86_64; rv:61.0) Gecko/20100101 Firefox/61.0" From the error_log: [Sun Jul 01 09:58:10.822889 2018] [proxy_http:error] [pid 1380] (70007)The timeout specified has expired: [client 192.168.0.240:56182] AH01102: error reading status line from remote server localhost:5762, referer: https://www.theotts.org/ledgersmb/login.pl?action=login&company=SalemStreetN [Sun Jul 01 09:58:10.822972 2018] [proxy:error] [pid 1380] [client 192.168.0.240:56182] AH00898: Error reading from remote server returned by /ledgersmb/is.pl, referer: https://www.theotts.org/ledgersmb/login.pl?action=login&company=SalemStreetN Current Centos OS level from uname -a: Linux wbointi7.theotts.org 3.10.0-862.3.3.el7.x86_64 #1 SMP Fri Jun 15 04:15:27 UTC 2018 x86_64 x86_64 x86_64 GNU/Linux Between 25 June and 1 July, the server hosting ledgersmb was updated, likely being the cause of the problem, but I have not found any issues I can attribute to this failure. Any help or suggestions are appreciated. -- Regards, Bill Ott Home: 919-363-0031 Cell: 919-434-7589 Email: Mailto:billott@theotts.org Website: http://www.theotts.org Profile: http://www.linkedin.com/in/wbott