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Troubleshooting



Three Computer Repair Books This is 162 pages, well written, with good humor and full of practical advice for the person starting out on a shoestring.


Title Date Comments
802.11g/n High Gain USB Wireless G / N Long-Range WiFi Network Adapter   2014 07 
- Boosting the signal at our vacation home -
Kerio Troubleshooting January 2014   2014 01 
- Looking at some Kerio related troubleshooting/support incidents from last month. -
Who's been reading my email?   2013 07  2013/07/02 DaveGillam
- The boss noticed that some emails he did not read were marked as read - who was responsible? -
An unusual DNS issue   2013 07 
- An unusual DNS issue threatens a paycheck -
Getting a list of recursive SPF records   2013 06  2013/06/28 TonyLawrence
- Should Kerio Connect have a function to automatically whitelist a valid SPF check? I think maybe they should. -
How to trouble-shoot file corruption   2013 07 
- If you don't have the space, you have to take running snapshots with fuser or lsof- that may not satisfy a very stubborn vendor who is convinced that *their* programs never screw up. -
Mysterious panics and freezes   2013 07 
- Crashes, panics and freezes: all work halts and you can't help being surprised. What just happened? -
Deleting a lost file name - delete unremoveable files   2013 07 
- It HAS a file name- it probably has control characters in it that are confusing the display. Try ls -b. If that doesn't work, do "ls -l > /tmp/t" and the "vi /tmp/t" -
View large files without more or less   2013 07 
- I have a rescue disk that doesn't include "more" or "less" - how can I examine large files? -
All about Telnet   2013 07 
- A collection of telnet related information and links. Telnet is seldom used today except for network troubleshooting. -
Pass-Through Printing   2013 07 
- The idea is that if the terminal sees a special key sequence, it will start sending the data out some other port (parallel or serial) until it sees some sequence that tells it to stop. -
Fixing an old SCO Unix 5.0.4 machine   2013 07 
- I found myself staring at an ancient Gateway and a screen hung at Enter run level (0-6, s or S) -
 
 
Samepage - Redefining how people create and share information
 
 
Wireshark 101   2013 05  2013/05/26 TonyLawrence
- Silly me. I really should have started using Wireshark long before this! -
Connect delete bug   2012 12 
- This is an unusual bug in the Kerio Connect 8 Web Client that few users are likely to see. -
Simple debugging with Kerio Control   2012 11 
- An easy way to use Control as a network sniffer by creating useless rules and adding Accounting logging. -
Understanding X-Loop forwarding headers   2012 11 
- How the X-Loop header works and how Cpanel apparently breaks it. -
Filtering and separating Kerio Control Debug logs   2012 10 
- Kerio debug logs can contain a lot of extraneous noise. Use a script like this to separate the wheat from the chaff -
Troubleshooting anti-spoofing messages   2012 10  2012/11/18 TonyLawrence
- Is this network congestion or some other problem? Can you see what is confusing me? Join me in a network troubleshooting problem. -
Troubleshooting Kerio Control installation   2012 10 
- Setting up Kerio control is usually very easy. If you do experience problems, this guide can help. -
Notes on Kerberos troubleshooting (Kerio)   2012 09  2012/09/18 TonyLawrence
- These are some notes on troubleshooting Kerberos, specifically in the context of Kerio directory service authentication. -
Kerio Connect crash dumps and the kassist Tool   2012 09 
- Kerio Connect crashes are rare, but if it does happen, this article will help you understand what to do. -
Moving an old SCO Unix Filepro box   2012 08  2012/09/18 TonyLawrence
- She thought she wanted to put a public IP address on this old SCO box. Fortunately, no one was able to help her with that. -
Setting up a multihomed Kerio Mailserver in a DMZ   2012 08 
- Missing a simple checkbox in the GUI network configuration prevented the mailserver from working in the DMZ -
Recovering from a bad Kerio Mailserver crash   2012 07  2012/09/17 TonyLawrence
- A RAID drive failure slowed the Kerio mailserver to a crawl and eventually brought it down entirely. More than 900 users without mail - what now? -
Query Kerio Custom rules   2012 07  2012/07/23 TonyLawrence
- A script to query Kerio mailserver custom rules or list by type. Partially useful on Windows with Perl or Cygwin. -
Fixing excessive user whitelisting   2012 07 
- A beta script for correcting unwanted entries in users Spam whitelist. -
Failure of encrypted connection Kerio Mailserver   2012 07  2012/07/20 TonyLawrence
- An unexpected cause to a failure to receive email from a customer momentarily baffles me. -
Kerio Troubleshooting   2012 05  2014/07/03 TonyLawrence
- There are only a very few things that will completely prevent Kerio Mailserver from starting. Usually this would come from a confused or mangled configuration file, but there are other conditions that can cause Kerio to refuse to start. -
Android phone crashes email account   2012 05  2012/05/18 Kanti
- A misbehaving Android phone caused a user to send duplicate messages - hundreds of them. We stopped that quickly by deleting her account on the phone (it's easy to recreate), but two weeks later her email stopped working -
Kerio Control Rip and Replace   2012 05  2014/07/10 TonyLawrence
- I tore out a perfectly good Astaro Firewall and replaced it with a Kerio Control box. The Astaro was only two years old and was working fine, but tearing it out made both me and my customer very happy. Read on to learn why. -
Support is not an annoyance   2012 05  2012/06/01 TonyLawrence
- Kerio's recent support changes have caused some customer backlash. I am sypathetic to some of these complaints, but I also see the necessity of the change and think it actually can be good for everyone. -
Troubleshooting Outlook KOC problems on new Windows 7 machines   2012 05  2012/05/04 TonyLawrence
- Troubleshooting can lead us down strange paths. Join me as we watch new Windows 7 machines act up after joining a domain. -
A Kerio Firewall transplant causes mail problems   2012 04  2012/04/06 TonyLawrence
- Moving a Kerio Control firewall to new hardware shouldn't be any trouble at all. In fact, it was not, but some red herrings led me to think that something had gone mysteriously wrong. -
Troubleshooting a scanner with an email gateway   2012 03  2012/03/28 NickBarron
- After an email conversion, the only problem was a scanner that could not send email. That should have been a simple fix, but we were led far astray. -
Where is the boing? (Mac scheduled startup)   2012 03  2014/04/06 TonyLawrence
- I first noticed the missing Mac startup chime a few weeks ago. It seemed very odd that if I rebooted, the chime did work - it was only the first boot of the day when it did not "boing". Starting up took too long also - something was wrong, but what? -
iPad recovery mode problem caused by bad backup   2012 03  2012/03/12 TonyLawrence
- When my iPad started crashing Thursday night, it looked like bad hardware. I was even more sure of that when I tried to recover from a backup and it crashed doing that. I took it to the Genius Bar and they agreed, but we all were wrong. -
Mysterious Duplicate IP problem solved   2011 11  2011/11/14 NickBarron
- I only needed to be run over by four or five cluetrains before realizing what was causing this 'IP address conflict' message on a Windows 2003 server. Follow along and see when you solve it. -
Local printing in Synchronics   2011 11  2012/03/06 anonymous
- I know exactly what he has - an old SCO Unix system with a Digiboard multiport serial board, green screen Wyse terminals and Okidata printers with serial cards. I can handle all of that. -
Do you hate your computer?   2011 09  2011/09/15 BigDumbDInosaur
- I knew someone who became so frustrated with a computer printer that he threw it down on the floor and jumped up and down on it until it was smashed to pieces. That's a bit extreme (and damaging to your bank account), but technology can make us feel like that, can't it? -
Basic Home Networking, Part 3, File and Printer Sharing   2011 08 
- The point of a computer network is sharing. You might not be sharing much, perhaps even only the Internet connection. If that's the end of it, you don't need much more than part one of this series, which deals with the setup of a basic small network. -
Putting the wrong name on a Win 7 user profile   2011 08  2011/08/25 NickBarron
- However, both of these new computer owners panicked at my suggestion. I explained that they just needed to cable up their new system; they claimed complete inability to do even that. Sigh. Yes, I know that this is mostly in their minds. It's a form of leaned helplessness. If they would just make a small effort, they probably could do this themselves, but they just stop and refuse to even try. It's too complicated, they are afraid that they might damage something or feel foolish. -
A few minor iPad set up problems baffle my neighbor   2011 08  2011/08/28 anonymous
- A neighbor took advantage of MA's recent tax free weekend and bought an iPad. He'd seen mine and his daughter had shown off hers the last time she had visited, so he had a pretty good idea of why he wanted it. Unfortunately, his initial experience was frustrating. -
Basic Home Networking - Part 2, wireless setup   2011 08 
- Often all that needs to be done is to tell your computer that you want to connect to a wireless network. It's not always that easy, but it certainly can be. However, even if it is that easy for you, you might still want to read the rest of this in case you have problems later. You also might want to read it because being "too easy" to get connected could mean that you are running some security risk and need to address that issue. -
Basic Home Networking - routers and switches   2011 08  2011/08/16 BigDumbDinosaur
- Setting up a small office or home network used to be a fairly complicated task. Aside from the technical knowledge needed, there was expensive equipment to buy and specialized tools for wiring. That's all changed - the necessary equipment is cheap and readily available and it's all very easy to configu re. -
A non-technical guide to understanding and fixing TCP/IP problems on a network   2011 08  2011/08/14 BigDumbDinosaur
- The title is a bit incorrect in the .non-technical. claim, because we are dealing with a geekish subject here and I can't avoid being a little "techie". -
Brother MFC-J615W printer   2011 08 
- I have never been a fan of inkjet printers. In fact. my general advice has been not to buy them because hey are far more expensive to operate than laser printer. These multifunction things have even more to dislike: if you lose part of the functionality, you are going to lose it all while it is out for repair. -
Perl Profiling with Devel::NYTProf   2011 07 
- I don't think I have ever used a profiler on my own code. The reasons are simple: I don't write much that is very complicated, so any bottlenecks are usually rather easy to spot. Most of what I do is ad hoc and limited use anyway, so speed is seldom a consideration. -
Internet phone service - without the service   2011 07  2011/07/16 BigDumbDinosaur
- My wife is one who, once on the telephone, can't seem to know when to stop ta lking. Accordingly, our residential phone service bill tends to bear a vague resemblance to the national debt. She can't seem to bring herself to change her phone habits, so I finally caved in against my better judgment and gave her the go-ahead to switch our residential service to voice-over-IP (VoIP). After doing a bit of research, a company called TeleBlend was selected to provision the service. -
Mysterious calendar in Kerio Webmail   2011 07 
- Troubleshooting a Kerio calendar: His calendar in Kerio also displays items from M's Google Calendar. This seems straight forward, except neither J or I set this up and both of our users c laim they don't know how it got set up this way. -
Why does fsck need a scratch file?   2011 04  2011/06/02 KenPorter
- Although fsck hasn't needed scratch files for a while, large disks are reopening that need. -
 
 
Kerio Connect Mailserver
 
 
Mysterious Duplicate IP addresses   2011 04  2011/04/20 TonyLawrence
- Proxyarp on smart switch causes sudden appearance of duplicate ip addresses: All machines on our 192.168.206.x subnet (mostly Mac's, with Windows servers) got the IP conflict message when they started up in the morning. We do have a linux dhcp server running on that subnet, but it only hands out 2 IP addresses for barcode guns, and those are given the IP based on their MAC address, so each barcode gun always gets the same IP and can move to other buildings without reconfiguring them, as they run in dhcp mode. -
The lowly ls command   2011 04  2011/04/20 TonyLawrence
- ls might have more flags than any other Unix command and operating system variance is wide. -
Three Computer Repair Books   2011 03 
- This is 162 pages, well written, with good humor and full of practical advice for the person starting out on a shoestring. -
Network Troubleshooting   2010 03  2010/03/16 AndrewSmallshaw
- As it turned out, the problem was very physical: a light fixture had fallen down and loosened some connections to a long forgotten ethernet switch. -
Disaster Averted   2010 03 
- He said it wouldn't shut off. I was a bit surprised that he was unaware of servers with power buttons that have to be held in for a bit to avoid accidental shutdown. -
When Samba Pigs Fly   2009 11 
- Yesterday a customer called because he needed to be able to write into a certain share on his Samba shares. -
More routers used as switches   2009 10 
- I got a good chuckle when he showed me the first printer. Only one network tap near where they put it so - he bought a router. -
Troubleshooting failed email   2009 08 
- You send email to someone at [email protected] and get something back about "The following addresses had transient non-fatal errors" -
An Unexpected IP   2009 08 
- Windows, Linux, Mac OS X, it would have all been the same: An old server had an OS transplant and needed to be connected to the network. -


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