When ColdFusion mail fails to deliver it will sit in the undelivr folder forever unless someone copies it back to the spool folder for another try. And even then mail that is actually invalid will just keep ending up back in the undelivr folder forever unless someone deletes it. If either of these folders end up with hundreds of thousands of files in them( which will happen eventually on a busy server), it will stop cfmail working and will affect ColdFusion's performance.

I am quite surprised Adobe have still not addressed this, especially considering they added a new feature to CF9 allowing you to view and MANUALLY respool failed mail, which is ok if you only have a few emails, but as it only displays like like 10 emails at a time, it is useless on a server that processes hundreds of thousands of emails per day.

Up till now I used a little VB script and a windows scheduled task to handle this, but I decided it was time for a CF solution that I could easily just plugin into the cfadmin.

So here it is, a custom extension for your ColdFusion administrator which allows you to specify how often you want to respool your undelivered mail and how long you want to keep trying for, after the retry limit is reached the undelivered mail will just get deleted.

FYI Railo retries sending mails by default.

DOWNLOAD HERE

readme.txt file in the download contains installation and setup instructions.

you can also turn on verbose output when manually running the scheduler to see what it is doing.

I may also add the option to send a failure notice to the sender for failed mails that get deleted.

If you want the ability to manually view/edit failed mail and send back to the spool then try Ray Camdens Spoolmail.

Change log

1.0.1  - 01/01/2012

Added logging with CFLOG
Added ability to edit/save scheduled task url

1.0.2 - 21/06/2013

Fixed some issues withthe respool task not deleting mails
Set the default url for task to use localhost
Added optional verbose output
Updated the readme

Has this crop up a few times, and there are all kinds of articles on the web giving complex workarounds which simply did not apply in my case.

The cause in my case was ColdFusion, specifically the wildcard (*)  handler mapping, because this handler tries to process the request first to see if the file being requested is CFML, if not then it returns the request back to IIS, which thus causes the above error.

The solution is simply to remove the wildcard handler mapping.

If you need to run CF and ASP.NET on the same site then you need to do so without the wildcard handler mapping. Unfortunately the regular handlers don't actually work as they point to jrun_iis6.dll , and I have no idea why they are even created, perhaps some legacy thing.

So you have to  change all the standard handlers (.cfm, .jsp etc) to point to the jrun_iis6_wildcard.dll instead of jrun_iis6.dll, and CFM pages will now work happily with ASP, PHP or anything else.

The current version of WebsitePanel does not setup the ColdFusion handler mappings correctly when you enable CF via the website properties page, it does not create the required Wildcard handler and instead only creates the regular individual file extension handlers.

This fix solves that problem and creates the wildcard handler instead.

The below zip contains 4 files, the 3 x .dll files need to be uploaded to each of your coldfusion servers in the root of the "websitepanel server" site. ths IIS60.cs file is the source code.

DOWNLOAD HERE

In response to Steve Bryant's post to have a "How I started in ColdFusion" day, here is my entry 

A very long time ago in a galaxy far far away (1998)  I got a lowly "web support" job for an ISP called Nacamar, it was a pretty low paid job and even though there was only 3 of us,most days I had nothing much to do as their senior web designer did everything, so I spent my time learning new stuff and generally fiddling/playing with webby stuff. I already knew basic HTML, JavaScript and CSS, but I wanted to learn something more and do some real coding. After the company Xmas party my opportunity arrived, the web designer got very drunk and managed to get himself fired due to his outrageous behaviour (at one point he actually jumped on the bosses back and attacked him LOL). This meant I was now the only web resource they had so I started to offer up my ideas of how to improve things. I managed to get my own office and my own development server setup and proceeded to investigate server side scripting technologies, there was not a lot of useful info on this topic back then, and while I may have briefly looked at CF, I think the info was rather sparse, Perl looked like a nightmare and so I opted to learn ASP and proceeded to make their website more dynamic, and also created a new intranet for them.
Not too long after this they employed a new Manager who I could only describe as "A corporate dick", he was prejudice against anything "different"  and so as you can imagine  my multi coloured mohawk did not go down well this chap.  So I decided it was time to move to pastures greener, and started job hunting. It didn't take long before I got an offer from a company called Redeye, a new startup, to help develop their new Analytics software using this technology called "ColdFusion".  So it was a learn on the job role, I had to learn CFML and Oracle (as well as SQL in general) while I was developing the App, which was no easy task I can assure you, especially as there was no real project spec, the only person who really understood what this app was supposed to do was the boss (Paul), and he could only really explain it to you from a business perspective rather than a technical perspective, so there was a lot of make it up as you go along and then rewrite it when it was wrong. I became proficient in CF quite quickly and really started to like it, it was definitely better than ASP I thought.

Then my 3 month review came up and I was rather surprised to be told by Paul that my work was not up to scratch and I was not producing results fast enough so he would have to let me go, which was disappointing as I did like it there, but it was quite a long trek every day. This however turned out to be a good thing thing as I walked straight into my next job at almost twice the salary and nearer to home. I also bumped into Paul some months later and he told me that he had been very wrong about me as every developer he had employed since had been no where near as good as me, did not grasp the concept as well and produced results at about half the speed, so it was clearly his expectations which had been too high, I didn't gloat (much), ok yes I did and I still am :-).

My next job was with a company called Online (now deceased) as a senior web developer. They did not use CF or in fact any technology in particular, they just had an exisitng  site which I was to build and maintain for a U.S. client who wanted to launch an ISP in the UK, which had a few ASP pages on it. This was the cushiest job you could possibly imagine, other than updating the odd page here and there, I had very little to do on a daily basis, I even built a rudimentary CMS for the ASP pages so the designers could update them themselves and reduced my workload even further. This gave me more time to play with CF, and this is when I really became part of the community and joined the UK CFUG discussion list and started answering every single question that was posted (it was quite active back then). It became quite comical because I was so fast at answering questions that often people would get my reply in their inbox even before the original post (not sure how). Spending so much time helping others is really what boosted my CF knowledge and skills to Expert or Guru level, I actually learned far more solving other developers problems than I did doing day to day coding. It was during my time here that I started CFDeveloper and became the first and only site to offer free CF hosting.
As new projects started within the company I of course did everything in CF and gradually replaced all the old ASP code, but eventually I saw Online's demise on the horizon even before they did and so again it was time to move on, which is  when I decided to start my first company Satachi back in 2000 doing ColdFusion development and consultancy and hosting, and then eventually led to CFMX HOSTING and now BlueThunder Internet.

I recent topic on CFGURU about clients who blame the technology rather than trying to diagnose the real problem reminded me of a couple of funny tech support stories I thought I would share where the client has incorrectly blamed ColdFusion/Hosting for their problems.

When is ColdFusion not ColdFusion, when it's PHP of course

I had a client (lets call him Dick) kept complaining that their site had stopped working AGAIN usually telling us there was a server problem and to restart CF as it was broken, every time I checked everything was working fine on the server, cf was working etc. They would never give us any more info about the problem other than that CF was broken.
It eventually turned out that they had got their site redeveloped some time ago  in PHP and also moved the hosting elsewhere as well, so not only was it not a CF site, but we were not even hosting it :-)

Every so often we will get another email from them saying they have problems with FTP, email or something, and each time we have to explain that we cannot help as we are not their host. Hopefully one day someone will update their records

2 sites are better than 1

Another client (lets call her Dizzy) emailed us to say that the changes she was making to her site were not showing up and ColdFusion must be broken. Bear in mind that we did not develop her site, so shouldn't be supporting it either really, but i'm such a helpful chap yaknow .
I got her to give me the URL of her admin interface, I logged in saw her changes, made some of my own changes, checked the site and there were the changes, no problems.
I couldn't understand why she couldn't see her changes, I got her to clear her cache, restart browser etc, after many exchanges of emails and phone calls, I eventually got her to send me a screen shot, at which point I noticed that the domain name was totally different to the one she sent me.
It finally transpired there were 2 different domains each hosting an exact copy of the site, one was hosted with us, one was hosted elsewhere.
When she edited her site, she did so on www.domain1.com/admin but then viewed the site on www.domain2.com, why I have no idea, but that was why she couldn't see her changes as she making them on a totally different site.

Unfortunately this happened every time she made changes to her site, she would contact us and we would go through this all over again.