I asked this question months ago, but I have new information so I'm going to treat it as a new problem and ask again.

Every day or 2 (but never more than once a day) I experience an odd hang on my desktop where currently running programs continue to run but I cannot start any new programs. For instance, my email client - Thunderbird - continues working. If my browser is running it mostly continues working (although see exception below). But clicking on a desktop icon does nothing. The start menu and first level of sub-menus display, but clicking anything (including the various power options) does nothing. Ctrl-Alt-Del is ignored. If I happen to select a Youtube video in my browser I get a "If playback doesn't begin shortly, try restarting your device" message.

At that point I usually wait a few minutes and then force a power off, restart, and everything works fine.

This problem has been happening both before and after a clean reinstall of Win10.

The problem happened this morning, and I was able to gather some new information.
  1. It started while I was trying to change a Google search argument in my browser. The browser hung up ("Not responding") for a while - maybe 30 seconds to a minute and then woke up. So I search for a Youtube video and got the message I mentioned above.
  2. I had other things to do so I walked away from my PC for about 15 minutes. Everything was working when I returned.


The Reliability History showed that during the hang my PC was (yet again!) trying to install .Net Native Framework Package 1.2.23205.0 and Advertising SDK for XAML. (There are a number of posts about this problem, but I haven's seen a solution that I'm brave enough to try. Maybe I'll get braver.)

The event log showed the following Application and System events either during or immediately following the hang:
Log Name: Application
Source: Microsoft-Windows-Immersive-Shell
Date: 5/28/2016 11:06:10 AM
Event ID: 5973
Task Category: (5973)
Level: Error
Keywords:
User: PUGET-116877\Patrick
Computer: Puget-116877
Description:
Activation of app Microsoft.Windows.Cortana_cw5n1h2txyewy!CortanaUI failed with error: The app didn't start in the required time. See the Microsoft-Windows-TWinUI/Operational log for additional information.
Event Xml:
<Event xmlns="http://schemas.microsoft.com/win/2004/08/events/event">
<System>
<Provider Name="Microsoft-Windows-Immersive-Shell" Guid="{315A8872-923E-4EA2-9889-33CD4754BF64}" />
<EventID>5973</EventID>
<Version>0</Version>
<Level>2</Level>
<Task>5973</Task>
<Opcode>0</Opcode>
<Keywords>0x2000000000000000</Keywords>
<TimeCreated SystemTime="2016-05-28T18:06:10.745271700Z" />
<EventRecordID>2888</EventRecordID>
<Correlation />
<Execution ProcessID="2520" ThreadID="2420" />
<Channel>Application</Channel>
<Computer>Puget-116877</Computer>
<Security UserID="S-1-5-21-4015337533-3340816402-3183025308-1001" />
</System>
<EventData>
<Data Name="AppId">Microsoft.Windows.Cortana_cw5n1h2txyewy!CortanaUI</Data>
<Data Name="ErrorCode">-2144927142</Data>
</EventData>
</Event>

Log Name: System
Source: Microsoft-Windows-DistributedCOM
Date: 5/28/2016 11:07:00 AM
Event ID: 10001
Task Category: None
Level: Error
Keywords: Classic
User: PUGET-116877\Patrick
Computer: Puget-116877
Description:
Unable to start a DCOM Server: CortanaUI.AppXtpp90jhw9p0njjb85kvhxpppgrqfp117.mca as Unavailable/Unavailable. The error:
"31"
Happened while starting this command:
"C:\Windows\system32\backgroundTaskHost.exe" -ServerName:CortanaUI.AppXy7vb4pc2dr3kc93kfc509b1d0arkfb2x.mca
Event Xml:
<Event xmlns="http://schemas.microsoft.com/win/2004/08/events/event">
<System>
<Provider Name="Microsoft-Windows-DistributedCOM" Guid="{1B562E86-B7AA-4131-BADC-B6F3A001407E}" EventSourceName="DCOM" />
<EventID Qualifiers="0">10001</EventID>
<Version>0</Version>
<Level>2</Level>
<Task>0</Task>
<Opcode>0</Opcode>
<Keywords>0x8080000000000000</Keywords>
<TimeCreated SystemTime="2016-05-28T18:07:00.597195100Z" />
<EventRecordID>2696</EventRecordID>
<Correlation />
<Execution ProcessID="436" ThreadID="9512" />
<Channel>System</Channel>
<Computer>Puget-116877</Computer>
<Security UserID="S-1-5-21-4015337533-3340816402-3183025308-1001" />
</System>
<EventData>
<Data Name="param1">"C:\Windows\system32\backgroundTaskHost.exe" -ServerName:CortanaUI.AppXy7vb4pc2dr3kc93kfc509b1d0arkfb2x.mca</Data>
<Data Name="param2">31</Data>
<Data Name="param3">CortanaUI.AppXtpp90jhw9p0njjb85kvhxpppgrqfp117.mca</Data>
<Data Name="param4">Unavailable</Data>
<Data Name="param5">Unavailable</Data>
</EventData>
</Event>

I don't know if those represent a cause or a victim, but I don't use Cortana so don't care how much trouble it has unless its problem effect the integrity of the PC.

Any ideas what I can do to correct or avoid this problem?