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Constant Crashes on Win 7 64-bit


smtp4dev crashes almost evertime mail is sent through. I'm running Win 7 64-bit and using PHP 5.3's email function on Apache 2.2. I don't see any log files or anything that might provide some insight into the issue in the installation directory. is there a way to do a crash report?
Closed May 6, 2011 at 7:39 AM by rnwood


icnocop wrote Jan 6, 2011 at 3:29 AM

This seems to be a duplicate of this work item:

schleichermann wrote Feb 3, 2011 at 3:45 PM

Same issue on a Windows 7 x64 when Ruby on Rails ActionMailer sends an email to SMTP4Dev.

When SMTP4Dev crashes and I click on 'show problem details' on the Window's application stopped working error dialog I get the following:

Stopped working

Problem signature:
Problem Event Name: CLR20r3
Problem Signature 01: smtp4dev.exe
Problem Signature 02:
Problem Signature 03: 4be9ca2f
Problem Signature 04: System
Problem Signature 05:
Problem Signature 06: 4a275e12
Problem Signature 07: 2bef
Problem Signature 08: 92
Problem Signature 09: System.ArgumentNullException
OS Version: 6.1.7600.
Locale ID: 1033

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wrote Feb 3, 2011 at 3:45 PM

wrote Feb 16, 2011 at 1:36 AM

wrote Mar 26, 2011 at 3:49 AM

Misagh wrote Apr 2, 2011 at 8:24 AM

win 7 x64 + IIS + 4 : same problem

wrote Apr 6, 2011 at 11:33 PM

wrote May 6, 2011 at 6:58 AM

wrote May 6, 2011 at 7:39 AM

dawidg wrote Jul 5, 2011 at 4:08 PM

Same problem: Windows 7 + smtp4dev = crash. Mail is sent from SQL mail.
It doesn't crash immediately. Sometimes it uses all the CPU it can get. I guess it's before a crash.

ipavlovi wrote Dec 5, 2011 at 1:24 PM

smtp4net crashes immediately after start.
Windows 7 64bit + .NET 4.0 + ASP.Net + IIS 7.0

I've tried both 2.0.9 and 2.1 alpha builds, result's the same

jgordon615 wrote Feb 6, 2012 at 5:14 PM

I had the same error so I downloaded the source and ran it in debug mode. Turns out that in my case smtp4dev was trying to retrieve a server certificate (for TLS) that didn't exist, so it crashed with the ArgumentNullException. My solution was to UNCHECK the "STARTTLS (Explicit SSL/TLS)" option in the Server tab of the options dialog.

Good luck to you.

wrote Feb 22, 2013 at 1:30 AM

wrote May 16, 2013 at 12:42 PM

JasonCrease wrote Oct 10, 2014 at 1:45 PM

@jgordon615 - yep - turning for STARTTLS fixed it for me. Thanks!