'show icon preview' not working, Icon preview no longer visible

Question

I have lots of folders full of jpg files. The preview icon do longer appears and all i get is the genetic icon. This happened randomly yesterday and I don't know how to fix it. I have the 'Show Icon Preview' enabled yet I only get the generic icon. Any ideas why? (OS X 10.5.8). I have tried a restart, permissions fix, and reindexed my hard drive with spotlight. No luck. Please help!
Simply: I don't know how to get the preview back even after selecting the "show icon preview" box on the options. HELP!

Answer 1

There probably are some hidden probable causes for this behavior;
while not knowing if you perform any general maintenance in a
preventative way for your OS X system, some of the suggestions
I could provide here may mean little or nothing to some users, or
to others, who have done them for years as a matter of course, to
suggest those could be the same as an insult; or a laughing matter.
You could try rather basic things, a few steps above 'repair disk
permissions' in Disk Utility. That's been around since OS 10.1.5.
And it has a place among other steps one can do to help out.
Sometimes, you can start up into SafeBoot mode; then choose to
run Disk Utility, and repair disk permissions. When done, quit D.U.
and restart the computer normally. - Other repairs to the system may
be performed by booting up from the OS X installer and run Disk
Utility from the menu drop-down options in the main Installer window.
You can repair disk, verify disk (SMART verify), repair disk permissions
and verify disk permissions. Plus other aspects of Disk utility that are
tools to set up partitions and other things beyond a basic simple fix.
SafeBoot mode, basic:
+Hold the Shift key down on start-up, keep holding it until you get a login+
+screen, enter admin password, then when desktop appears, you can+
+use GO in menu bar to find Utilities folder, and run Disk Utility's repair+
+disk permissions. When done, quit the Utility and restart.+
There probably may be some .plist file controlling the view of image icons
and since I haven't followed that issue (experienced it in the past, forgot
what I did to fix it) I am not sure what preference file to suggest trashing.
But you can be very selective, when knowledgeable, and do that. Then,
later on, when you restart the computer the default setting would return.
You could set that to whatever (if not the default) & that may fix the matter.
{One preference file location that probably would contain your user account's
.plists would be in the Macintosh HD> User folder> Library> Preferences>
...Now, the correct one among these becomes important. There is a desktop
plist, a finder plist, and others. Since each user in a Mac with their own setup
account can change these, yours should be in your booted user account.
However, some time has passed since this kind of issue occurred and I didn't
need to delete a .plist to resolve it. Yet that may be a short fix.}
These issues usually have a cause; sometimes it may be due to other items
not quite right in the user interface and symptoms of that sometimes show up
in odd places and they may not be directly related. Subtle and dismissed, a
few of those quirks are not show stoppers in OS X. A 'safeboot' & disk utility
may resolve some; to find a correct .plist preference file & trash it may, too.
If the computer's hard disk drive is getting full of content you have added, it
may be time to archive image libraries and/or music libraries off the Mac's
internal hard disk drive and then thin out content on the computer. That can
help a computer run better. Damage to data on the computer drive may be
a result (or outright is) of over-filling the hard disk drive. Overwriting content
is sometimes an issue; it could be subtle, too, for awhile. Checked into it?
For some preventative maintenance chores, I have and use OnyX which is
a free running utility tool (which I refer to as a utility interface tool) that pulls
the strings in OS X that some users would not think of the Terminal utility
ways of making them work; this gives you a GUI format, an application to
run various sets of items rather easily. If done without concern, these tools
can do bad things (same as booted Disk Utility, drastic tools are onboard.)
OnyX is a free-running downloadable app from Titanium Software; and since
I only use it maybe once every several months (or sooner if bored or if active
in using one computer more than usual) & have it run in Automation selection
having chosen all the check-box choices, so it will do those. I also have OnyX
set in its preferences, to restart the computer after it is done running those.
This may do more than you need in this selection of Automation. I have never
had any issues with this; but some preference choices system-wide may need
to be set back to your choice, as it can be also set to wipe caches or other old
logs and misc stuff. A few settings won't make much different to default from.
Usually, I prefer not to shut off or restart my computer until such time as when
Activity Monitor shows some issue with virtual memory and swap files or space
on the hard drive being excessively allocated as Virtual Memory. At times, a
restart may be required. My Mac can run a few months without restart, but it is
left to sleep or I will put it to sleep. Even so, some basic background OS X items
may not automatically run as they should. You can force the maintenance cycles.
If the 'show icon preview' does not work even after performing catch-up maintenace
and including OnyX, SafeBoot, and others; and if you have at least 30% of the total
hard disk drive capacity open or free from use, then you may have to consider a few
other ideas. (Removing the plist file may be the only thing you'd need do.) Another
idea in a few cases of more severe odd behavior, and if you updated your Leopard
10.5 to your current/last level through use of the Delta or small update file, would be
to get the larger Combo (last version) and after repairing disk permissions, install it
over the similar system in your computer. 10.5.8 over 10.5.8. Then restart and go in
and repair disk permissions again. Perhaps later on, safeboot and do them.
That much effort is seldom needed. Preventative maintenance and care to not over-
fill the hard disk drive, helps to almost never see such a problem in your Mac OS X.
{In a few cases, people who have upgraded from an earlier OS X version (Tiger-to-
Leopard, for example) and had a problem, may still have a similar problem later. So
it is best to fix issues and not hope to upgrade over them. Unless it is a totally new
bare-bones secure zero-overwritten drive, correct partition map, reformat, new install.
Then, there should be no doubt if there was an odd problem in the software, only.}
Hopefully some of this late night rambling may be of some help.
+Answering a question in these forums can be like replying to a+
+statement thus, "why won't my car go?" And an answer starts+
+out by asking dozens of questions about the car itself and the+
+status of the car, if it has fuel, tires, if it's been in a flood, or if+
+there is an engine, fuel, battery... At least I know yours runs!+
Good luck & happy computing!