Edited Issue: Null reference exception on startup [63930]

When launching application I can see message "Loading recent tenants and sites..." then null reference exception is thrown.

here is the log file:

```
Time;Machine;Process;Version;Category;EventId;Level;Correlation;Message
23-08-2015 11:04:59.415;SP2013DEV;SPCB.exe;1.7.0.0;General;0;Exception;73cdc001-4954-4e67-bead-b2aeae5b02d3;Error while retrieving default browser setting.
23-08-2015 11:04:59.431;SP2013DEV;SPCB.exe;1.7.0.0;General;0;Exception;73cdc001-4954-4e67-bead-b2aeae5b02d3;System.NullReferenceException: Object reference not set to an instance of an object.
23-08-2015 11:04:59.431;SP2013DEV;SPCB.exe;1.7.0.0;General;0;Exception;73cdc001-4954-4e67-bead-b2aeae5b02d3; at SPBrowser.Utils.BrowserUtil.GetBrowsers()
23-08-2015 11:04:59.431;SP2013DEV;SPCB.exe;1.7.0.0;General;0;Exception;73cdc001-4954-4e67-bead-b2aeae5b02d3; at SPBrowser.Utils.BrowserUtil.GetSystemDefaultBrowser()
23-08-2015 11:04:59.431;SP2013DEV;SPCB.exe;1.7.0.0;General;0;Exception;73cdc001-4954-4e67-bead-b2aeae5b02d3;Object reference not set to an instance of an object.
23-08-2015 11:04:59.431;SP2013DEV;SPCB.exe;1.7.0.0;General;0;Exception;73cdc001-4954-4e67-bead-b2aeae5b02d3;System.NullReferenceException: Object reference not set to an instance of an object.
23-08-2015 11:04:59.431;SP2013DEV;SPCB.exe;1.7.0.0;General;0;Exception;73cdc001-4954-4e67-bead-b2aeae5b02d3; at SPBrowser.Utils.BrowserUtil.GetBrowsers()
23-08-2015 11:04:59.431;SP2013DEV;SPCB.exe;1.7.0.0;General;0;Exception;73cdc001-4954-4e67-bead-b2aeae5b02d3; at SPBrowser.Utils.BrowserUtil.GetBrowser(String name)
23-08-2015 11:04:59.431;SP2013DEV;SPCB.exe;1.7.0.0;General;0;Exception;73cdc001-4954-4e67-bead-b2aeae5b02d3; at SPBrowser.Configuration..ctor()
23-08-2015 11:04:59.431;SP2013DEV;SPCB.exe;1.7.0.0;General;0;Exception;73cdc001-4954-4e67-bead-b2aeae5b02d3; at SPBrowser.Configuration.get_Current()
23-08-2015 11:04:59.431;SP2013DEV;SPCB.exe;1.7.0.0;General;0;Exception;73cdc001-4954-4e67-bead-b2aeae5b02d3; at SPBrowser.Utils.LogUtil.TruncateLogFiles()
23-08-2015 11:04:59.447;SP2013DEV;SPCB.exe;1.7.0.0;General;0;Exception;73cdc001-4954-4e67-bead-b2aeae5b02d3;Error while retrieving default browser setting.
23-08-2015 11:04:59.447;SP2013DEV;SPCB.exe;1.7.0.0;General;0;Exception;73cdc001-4954-4e67-bead-b2aeae5b02d3;System.NullReferenceException: Object reference not set to an instance of an object.
23-08-2015 11:04:59.447;SP2013DEV;SPCB.exe;1.7.0.0;General;0;Exception;73cdc001-4954-4e67-bead-b2aeae5b02d3; at SPBrowser.Utils.BrowserUtil.GetBrowsers()
23-08-2015 11:04:59.447;SP2013DEV;SPCB.exe;1.7.0.0;General;0;Exception;73cdc001-4954-4e67-bead-b2aeae5b02d3; at SPBrowser.Utils.BrowserUtil.GetSystemDefaultBrowser()
23-08-2015 11:05:13.362;SP2013DEV;SPCB.exe;1.7.0.0;General;0;Exception;73cdc001-4954-4e67-bead-b2aeae5b02d3;Object reference not set to an instance of an object.
23-08-2015 11:05:13.362;SP2013DEV;SPCB.exe;1.7.0.0;General;0;Exception;73cdc001-4954-4e67-bead-b2aeae5b02d3;System.NullReferenceException: Object reference not set to an instance of an object.
23-08-2015 11:05:13.362;SP2013DEV;SPCB.exe;1.7.0.0;General;0;Exception;73cdc001-4954-4e67-bead-b2aeae5b02d3; at SPBrowser.Utils.BrowserUtil.GetBrowsers()
23-08-2015 11:05:13.362;SP2013DEV;SPCB.exe;1.7.0.0;General;0;Exception;73cdc001-4954-4e67-bead-b2aeae5b02d3; at SPBrowser.Utils.BrowserUtil.GetBrowser(String name)
23-08-2015 11:05:13.362;SP2013DEV;SPCB.exe;1.7.0.0;General;0;Exception;73cdc001-4954-4e67-bead-b2aeae5b02d3; at SPBrowser.Configuration..ctor()
23-08-2015 11:05:13.362;SP2013DEV;SPCB.exe;1.7.0.0;General;0;Exception;73cdc001-4954-4e67-bead-b2aeae5b02d3; at SPBrowser.Configuration.get_Current()
23-08-2015 11:05:13.362;SP2013DEV;SPCB.exe;1.7.0.0;General;0;Exception;73cdc001-4954-4e67-bead-b2aeae5b02d3; at SPBrowser.Program.Main(String[] args)

```

I looked into the code for method `GetBrowsers`, trying to run it on my environment and find that it fails under line

```
RegistryKey browserKeyPath = browserKey.OpenSubKey(@"shell\open\command");
var Path = (string)browserKeyPath.GetValue(null).ToString();
```
`browserKeyPath` is null, that's why null reference is thrown. I looked into my regedit and find that I have mystic Tourch browser installed without `shell\open\command` subtree. (see attach). After deleting all works fine. I think it will be good if you can include additional check in your code to prevent such situations.

Thanks!
Comments: ** Comment from web user: BdeJager **

Thanks for the research! I added exception handling and will silently drop the browsers, who cause an exception. Otherwise I have to support all exotic registry entries related to browsers. Browsers like Internet Explorer, Google Chrome and Firefox all have the registry entry 'shell\open\command'.

Sorry to not support Torch as an alternative browser in SPCB. When it's your default browser, it should work fine!

The fix is included in the next release.