Distinctive Ringing for Internal Extensions with 3CX and Yealink

Mark Berry April 19, 2017

A customer using 3CX v.15 with Yealink T42S phones would like calls from internal extensions to have a distinctive ring.


April 2017 Monthly Rollup Breaks VB6 App

Mark Berry April 12, 2017

I maintain a client-server database app written in VB6 that uses ADO and COM+/DCOM. After installing the “April, 2017 Security Monthly Quality Rollup,” the VB6 app crashes in msado15.dll and ntdll.dll when trying to write to to the database. Uninstalling the update restores full write functionality. This is verified on Windows 7 x86 and Windows 8.1 x64. The issue is also present in Windows 10 x64 but I’m not testing that further.

Let me know if you encounter a similar issue and if you find a solution!


Restore Server to Desktop – 2017 Edition

Mark Berry March 23, 2017

Once a year, I test restoring a server to a desktop. The server is backed up with standard Windows Backup. The idea is to confirm that if the server went down, I could quickly restore to one of the customer’s desktops as a temporary solution while the server is repaired or replaced. This is also an interesting test of how well Windows Backup handles restoring to different hardware. Previous tests are blogged in 2011, 2012, 2013, 2014, 2015, and 2016.


Disable SIP ALG on Tomato Shibby

Mark Berry March 16, 2017

A PBX vendor like 3CX may tell you to disable SIP ALG on your router.

I’m running Tomato on my router, specifically Tomato Firmware 1.28.0000 MIPSR2-132 K26 Max. With the help of this thread, I checked and disabled SIP ALG.


Use Certutil to Get File Hash

Mark Berry March 9, 2017

I have been happily using the tiny Bullzip MD5 Calculator to quickly get an MD5 hash directly from the context menu in Windows Explorer.

But what if you need a hash on a where Bullzip isn’t installed? Or a different hash?


WSUS Kills Itself with KB3159706

Mark Berry March 4, 2017

After deploying WSUS on a Server 2012 R2 Essentials machine, I allowed WSUS to update itself with KB3159706. This upgrades WSUS to supply Windows 10 upgrades (not in use at this location) but the more obvious effect is that it kills WSUS:


Cloned PCs Disappear in WSUS

Mark Berry March 2, 2017

Just set up WSUS in an environment with a few cloned PCs. One PC would show up in WSUS, then it would disappear when a cloned PC showed up.

The issue is a duplicate registry key:



3CX SBC Invalid signature received: 0x10317

Mark Berry February 23, 2017

I’m using 3CX Session Border Controller (SBC) 15.0.56341 to connect to a 3CX v15 SP4 server running on Server 2012 R2 in the cloud. Usually it works fine. A couple days ago, though, even after re-starting the SBC, I was getting the error "Invalid signature received: 0x10317".



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