Created attachment 66019 [details]
Screeshot showing the error message.

I have just installed LO-3.6.1.2 build on Windows 7 Professional, 64-bit and saw the following scenario:

1. Double clicked the LO-3.6 icon.
2. Waited few second (10 or so) and nothing happened (no splash screen).
3. Double clicked the LO-3.6 icon once again.

Result: The following error message appeared on the screen, see also the screenshot:

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Unhandled exception:
cannot remove file
file:///C:/Users/pmladek/AppData/Roaming/LibreOffice/3/user/extensions/bundled/registry/com.sun.star.comp.deployment.help.PackageRegistryBackend/luh6gap.tmp/ks/caption/com.sun.wiki-publisher%252Fwiki.xhp: 2
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Few seconds later, the splash screen appeared. It started to register the extensions and the application started.

So, there were evidently running two instances. One of them failed and the other succeeded.


Possible explanation:
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The first instance was removing the huge bundled extensions directory before showing the splash screen => it looked like the application was not started => I started another instance => both instances started to remove the same files => one instance was "slower" and failed


Possible solution:
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+ show splash earlier
+ earlier detect that another instance is running
+ ignore this

Note that we install many extensions by default and the cache is huge. So, more users might be affected.