If your question is not here, try the User Guide to reveal MysticThumbs' inner workings.
Troubleshooting articles with how-to's
Q: Is there a help system or manual?
A: Yes - Pressing F1 in the control panel will bring up contextual help. There are also contextual tool tips in the control panel and a User Guide.
Q: Thumbnails aren't working immediately after install?
A: Restart Windows to make sure the thumbnail cache is unlocked and ready to work.
Q: Thumbnails don't seem to work in OneDrive folders. What's wrong?
A: Check your OneDrive settings and disable 'Files on Demand' if required. This option is a trick that OneDrive does to put empty placeholder files on your desktop until you 'demand' a file, thus the file can not be thumbnailed until it is fully downloaded.
Q: Thumbnails aren't working browsing through Symbolic Links (symlink) on Windows 8?
A: Unfortunately this is a known bug in Windows 8. A Workaround is to browse directly to the network UNC location in Explorer.
Q: Why are some or all of my thumbnails being remade every time a folder is opened?
A: A number of reasons can cause this. Browsing over network can sometimes cause it - see 'delete thumbs.db' in help. Encrypted folders will always force thumbnails to be remade. A corrupt thumbnail cache can cause this. Use 'clear thumbnail cache' in the control panel; see User Guide.
Q: Some PSD images don't show a thumbnail?
A: Check the images were either saved with 'Maximize Compatibility' option or with 'Embedded thumbnail' option in the preferences of Photoshop.
Q: Why do some images not generate a thumbnail?
A: Check the 'Maximum Dimension' and 'Maximum Size' options in the control panel.
Q: Why isn't SVG making thumbnails correctly or at all?
A: For maximum compatibility, SVG requires Internet Explorer 9 and Windows 7 or better. On older systems another engine is used with only minor compatibility.
Q: Why aren't PDF, AI, PS or EPS files making thumbnails?
A: These files are Postscript based. They require Ghostscript to be installed. An option to install this is offered when installing MysticThumbs.
Q: Why arent Postscript based files (PDF, AI, PS, EPS) generating thumbnails in some applications open/save dialog boxes?
A: On 64 bit operating systems, the 32 bit Ghostscript DLL is used when running within a 32 bit applications open/save dialog box. Install the 32 bit Ghostscript as well as the 64 bit one.
Q: What if I don't want some file types to be thumbnailed by MysticThumbs?
A: You can select individual file types or extensions in the control panel and individually disable them. If there was another thumbnailer installed for that extension when MysticThumbs was installed, the original thumbnailer is restored when disabling. See the help for more information.
Q: Windows / Explorer sometimes stalls or locks up when generating thumbnails?
A: Some images require a lot of processing overhead to generate a thumbnail. If you find Windows becomes sluggish when thumbnails are being made, try enabling the 'low process priority' option in the control panel. Also try pressing F5 within Explorer or using the 'Refresh Explorer' context menu from the MysticThumbs notification icon to see if Explorer has become stuck for some reason.
Q: Where is the thumbnail cache on Windows Vista and newer? Can I delete it manually?
A: The thumbnail cache is comprised of a few system locked files on Windows Vista and above, stored in the User data area. The only supported way of deleting or cleaning it is using Disk Cleanup or the 'Clear Thumbnail Cache' option in the MysticThumbs control panel, which invokes the system cleanup tool (see help). 'thumbs.db' files similar to Windows XP are not used anymore except when browsing network folders (see 'thumbs.db' option in the MysticThumbs control panel.
Q: CorelDraw (.cdr) thumbnails not behaving correctly?
A: CorelDraw suite of tools installs it's own thumbnail handler which can interfere with MysticThumbs. From 'Programs and Features' control panel, find and uninstall 'CorelGraphics Windows Shell Extension' and MysticThumbs should take control again. Warning - This may have other consequences in the Shell depending on the functions of the CorelGraphics Windows Shell Extension.
Q: Why there is no support for 3D and CAD file types such as: OBJ, STL, STP, DXF, MudBox etc?
A: The reason for a lack of support for CAD files in general, but specifically those types are the lack of
embedded thumbnails within the files. For 3D formats such as these, there is no specific image of the file,
and without an embedded thumbnail included (for example 3ds Max does include one in .max files and is supported) it essentially
requires a fully blown application to load and render the files into a 2D image.
Even if this were generically possible (say for simple .obj files) there are further problems,
such as where to render the image from, what part to render, how back-faces are handled, materials and texturing, etc.
It becomes a very large and indeterminate problem. For this reason, MysticThumbs does not attempt any 3D files without
access to an embedded thumbnail or there would be at the very least, a lot of complaints from users that "they look wrong".
If you are aware that any of these formats do have the capability to carry an embedded thumbnail - and know where to get
access to the file format specification - then please let us know and we'll look into it.
If you have lost your license key you can request it be emailed to you from
Occasionally, a Windows MSI based install can become corrupted due to a number of random factors such as:
When this happens you may receive an error whilst installing, updating or
uninstalling a product asking you to contact customer support, and the install
will refuse to complete.
Follow these instructions to completely remove and repair the damaged install.
Once removed you will be able to install the latest version without any problems.