Just had to deal with a pretty mysterious issue when my Sitecore app stopped staring up for whatever reasons.
Symptoms:
- nothing happens, browser just hangs with the “Connecting…” message - nothing in the Sitecore logs - nothing in the Event Viewer - nothing unusual on the SQL side - nothing unusually heavy on the worker process – CPU is idling out, memory is fine.

In overall, a sign that something is inherently wrong.

Well, I don’t know what I would do if not . Fired that guy up, setup to filter all events related to the w3wp.exe, and here we go. Search subsystem built on Lucene was trying to write some temp files to c:\windows\temp and had no access:

So I went ahead and cleared up everything from c:\windows\temp, ensured that Network Service (in your case current app pool account) has read/write permissions, then restarted the app pool and that was it!

To check for all file system level permissions necessary for Sitecore to operate, use the .

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