@WZZZ Thanks for replying. Unfortunately I forgot to say I'm on Office 2011.
@senzaesclusiva I'm assuming you're referring to Office 2011 updated to the latest release (14.3.4). Even though the qlgenerator file did never get updated (at least I think so, as both creation and modification dates are January 27, 2010. Version 2.0). What's going wrong with fonts installation? I noticed that until a couple of updates ago every time I updated Office 2011 I got duplicated fonts which I had to resolve. But now updates work smoothly.
Yes i'm referring to Office 2011 updated to 14-3-4.
Often i install free fonts to try them in a websites develop and i do it always without problems.
At the moment when a try to install a new font, font library windows "blinks" like a butterfy and does not
install any new font.
It's the first time that i have a so "strange" behaviours of SL, and what do me angry is not to understand what could be happened and how to solve it.
At this point i dubt also that a new installation can be usefull.
What do you think about ?
I'm afraid we're drifting off topic (this one should be about quick look). If you install plenty of fonts, maybe one or more are corrupt or you installed too many. If you didn't yet try, the first thing I suggest is booting in Safe Mode (press and hold Shift at startup). This will clear your font cache. I'm no font expert, but here you can find detailed information about troubleshooting fonts in Snow Leopard:
http://www.office.mvps.org/troubleshoot/bad_font.html (a bit dated maybe)
There are many useful discussions in the Communities; this one for example:
https://discussions.apple.com/thread/4275474?start=0 which links to an exhaustive article by user Kurt Lang about font management:
At last I resolved to install anyway this security update and thought to report in case someone else is waiting for clues. Quick look preview for Office files keeps working fine (Office 2011 v. 14.3.5): I can see previews of Word files no matter which version of the application created them. There's a glitch with Excel files, but I can't tell for sure, maybe it's always been there (I seldom use Excel). It seems that quick look previews are available only for Excel files created in Office 2011; anyway they aren't for old files created with Excel v. X, I haven't .xls from Office 2004 or 2008 to test. However I can restore quick look preview just "saving as" a copy in Excel 14.3.5. I don't use at all PowerPoint.
Hi Yeehat and thanks for your replay.
Doing my MacBook Pro is a production machine i preferred to not waste more time to proof understand the issue and try to solve it by a workaround.
So i have reinstalled SL and it's last combo update, repaired system permission by installation disk. Now all works fine and have had no problem with applications and other settings. Magic: no loss of data or app settings. Now Office file quick look previews all files (old and new).
Font Library also works well, except about a font that which it's probably corrupted (or not compatible even if it seems to be)
At the moment i've not installed the last security update...I'm too afraid of having to start all over again :-)))
First I'll try to read up best on solutions in case Quick Look do still the same issue.
I know that it is not a "solution" but i was wasting too much job time. I think i will survive a few more weeks without it !!! :-)