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Courier IMAPd and warnings

After installing an ISPConfig deployment, everything seemed to work properly, but every now-and-then I got this weird error that there was something wrong with the mail server configuration. The Apple showed a exclamation mark with the following message:

The server returned the error: The attempt to read data from the server server.domain.ext failed.

Some research showed that the Apple mail clients tend to open several connections for IMAP, and the default setting of the Courier IMAPd server is to allow (only) 4 connections from the same IP address.

Modifying the Courier config file (/usr/lib/courier-imap/etc/imapd) and allowing e.g. 20 connections from 1 IP address solved this problem.

#  Maximum number of connections to accept from the same IP address


#  Maximum number of connections to accept from the same IP address


 If your company / household holds several imap mail clients you may need to increase the counter even more (65536 is the maximum amount of connections for ANY IP address).

If you have SSL enabled on the Courier IMAPd server you also need to add the MAXPERIP variable to the imap-ssl config file (/usr/lib/courier-imap/etc/imapd-ssl).

Finally, you need to restart the Courier IMAPd services (/etc/init.d/courier-imap restart)


Changing SSL Certificates in a ISPConfig v3 Configuration

When you install a Perfect Server based on Centos and ISPConfig v3.x, the system / 'installer' creates for the components self-signed certificates. All these certificates will generate different warnings in your browser, mail clients etc. So time to eliminate those warnings.

First I needed to find out where all those certificates are located, and what there formats are. In my case, there are three services that use SSL/TLS in some form;

  1. Postfix SMTP service
  2. Courier IMAP service
  3. http / Apache2 webservice

Checking the configuration files will reveal their locations.

Click to read more ...


Getting ISPConfig to Work on Centos

This is not a manual describing the installation (pre-requisites) of ISPConfig software on a Centos platform. An excellent manual can be found online. It's just that I ran into a problem when I tried to connect an e-mail client to the (IMAP) mailserver (controled by ISPConfig). All the appropriate ports / listeners were up and running, so it had to be a configuration issue.

Googling around didn't solve my problem. My collegue, Xander (@xmoments /, cam eto the rescue with the solution;

yum install cyrus-sasl-plain-2.1.23-13.el6.x86_64

Software that handles cleartext passwords between mail processes. After the installation, the mail went flying across the Interwebs.


Screen Capture Can't Be Saved

After upgrading my iMac to OS X Lion (10.7) everything works (or at least seems to work), until I tried to do a screen capture with the built-in tools.

Things that worked:

  • Capturing the entire desktop to file
  • Capturing a selection (using the cross-hair) to file
  • Capturing the entire desktop to the clipboard
  • Capturing a selection (using the cross-hair) to the clipboard

Things that didn't work:

  • Capturing entire windows to file or the clipboard (SHIFT-COMMAND-4 + SPACE / SHIFT-COMMAND-3 + SPACE)

All I got was a weird notification box with the message:

Screen capture can't be saved

The console application also showed an error message:

12/16/11 1:40:08.762 screencapture could not capture window 3c

Lurking around the Interwebs, I found this seem to occur after an upgrade of the OS, but real solutions are hard to come by.

This is what I did to solve my problem:

  • Remove the screencapture PLIST (preferences) file (~/Library/Preferences/
  • Copy a file from a working OS X Lion environment and place it in the correct location on the troubled OS X installation.

That seemed to result in two files (one with an additional extension of .locked). I removed the .locked file, rebooted the iMac, and screen capture worked again.

I must mention that I didn't see the .locked file initially. Could be that it existed before. In which case I probably did more than was required to get things fixed....


Leica M and Lens Caps

Normally, I would have posted the following video in the Leica diary section, but that section is about totally serious Leica subjects only ;-). What the guy in this video is demonstrating (I hope) to the videographer, is that it's easy to forget that you put the lens cap back on the lens. With (d)SLR's you don't have this problem, since you're looking through the actual lens (unless you're blind or shooting in pitch black).

Fairness to say that I've had it happen to me a couple of times, but I notice my mistake at the moment I press the shutterbutton (+3sec exposure in broad daylight?? Must have forgotten something...).


A (slightly biased) review of the Samsung Galaxy S2 Phone

Updated on Friday, January 20, 2012 at 14:58 by Registered CommenterWillem

My employer decided to give its employees new smartphones. Mostly because we've been begging for them the last couple of years. Unfortunately, not the one(s) we (or perhaps I) have been asking for.

In my line of work I come across customers with wireless networks that need (some sort of) security in place. The only real question I get during those projects is; "Will it work with an iPhone or an iPad?" In my entire career, I haven't had a single question of that kind regarding Android or Windows Mobile phones.... There's no denying it; the iOS devices from Apple are huge. Even in the corporate market.

So, no corporate iOS device for me. Instead, they shipped the Samsung Galaxy S2 (listed as iPhone look-a-like) to me.

Click to read more ...


Billingham Hadley Small Review

After I bought the Leica M9, I was in the market to get a new camera bag for the M9. The bag had to be small, versatile, and not scream '(expensive) PHOTO GEAR HERE!!!!'. Since I owned a Billingham bag before, my eye quickly fell on the smaller Billingham bags. Especially the Hadley Small looked very appealing. After checking the internal and external dimensions on the website I purchased the bag (Black FybreNite version) through Robert White in the UK. They had the bag in stock, and it was cheaper (with shipping included) than ordering it in the Netherlands. I also included the SP50 Shoulderpad, for additional comfort.

Click to read more ...


Upgrading Splunk on Ubuntu Linux

Just a small post with the instructions on upgrading Splunk on Ubuntu Linux.

First download the Splunk update. The Splunk website also gives you the wget command, which you can use directly on the Linux commandline.

Click to read more ...


Camera Club Photo Weekend 2011

This weekend, we had a little outing with the camera club in Drenthe (NL). During the weekend we visited Orvulte, Camp Westerbork, Dwingelderveld, and Groningen.

  • Orvulte is a (really) small town with a no-cars-allowed-policy during a large part of the year. It could be a nice place to visit if it wasn't overrun by tourists (and photographers).
  • Camp Westerbork was a transit camp for Jews during the second World War. Over 107.000 Jews, Sinti and Roma were shipped to various concentration camps in Europe and lost their lives. Unfortunately, there's not much left of the original camp.

Barbed Wire @ Camp Westerbork

Iconic rail track @ Camp WesterborkNice autumn colors during the walk to the camp

  • National Park Dwingelderveld is a small nature reserve in Drenthe (NL).
  • And Groningen is.... well a big city in the northern part of the Netherlands.

Waiting for the busRed, White and GreenThis was the first (photo)trip without my Nikon dSLR gear. Leica only, which was kinda challenging at times (not having zoom-capabilities etc.), but I survived.



Unofficial iOS5 upgrade

After reading the iOS5 upgrade on the Lifehacker website, I decided to upgrade my iPad2 to iOS5. It's unofficial, because iOS5 hasn't been released yet. The version mentioned on the Lifehacker websites is considered to be the Gold-Master version. Meaning that it's the final version, waiting to be released somewhere this month.

First I installed the iTunes beta version as mentioned and downloaded the appropriate iOS versions for my iPad and iPhone. The upgrade went extremely well. Just remember to backup your device before the 'upgrade' proceding.
After the iPad upgrade, I decided to upgrade my iPhone3gs. This went as smooth as the iPad upgrade.

The biggest new feature for me so far is the possibility to use custom text/notification tones. The iPhone3gs also feels more responsive.

There was one annoyance with the initial configuration of the iPad;
My Apple ID was a basic username, and not an e-mail address. This is NOT accepted by the initial iOS5 configuration wizard. Your Apple account NEEDS TO BE an e-mail address. It took me a while to set that up properly in my online account settings.