allow_context_menus

Yes

List of context menu extensions that Opus will ignore errors from. Normally Opus blocks context menu extensions that cause an exception - you can override this by adding the context menu's GUID to this list. The GUID for each context menu extension must be listed on a separate line. You can use the context_menu_debug option to discover a context menu's GUID.

amiga_icon_palette

Palette to use when displaying legacy Amiga icons.

cd_thumb_coverart_file

Folders containing this file always display as CD albums in thumbnails mode, regardless of other content. The default is coverart.jpg.

collection_change_delay

Delay (in milliseconds) before processing external delete/rename operations in File Collections. You might want to increase this if you find that files are disappearing from your file collections when you edit them in other programs (e.g. Word).

compress_collections

Compress File Collections to save disk space. If turned off, File Collections will be saved as uncompressed XML files - if you have a lot of files in a collection, this can make the files take up a lot of space.

convert_descriptions

Convert old description files to the descript.ion format. Unless you are migrating from an extremely old version of Directory Opus you should never need to set this.

copy_nonbufferio_threshold

File size threshold above which file copies to or from local devices will be performed in non-buffered mode, where the filesystem buffers provided by Windows are bypassed. Units can be KB, MB or GB. If no units are specified, defaults to MB.

For very large files, copying in non-buffered mode can increase the memory efficiency, copy speed and UI responsiveness. On the other hand, non-buffered mode may slow things down for smaller files or certain devices. In rare cases, non-buffered mode may not work at all (e.g. if you have a device which mis-reports its sector size).

Set the value to 0 (zero) to disable non-buffered mode.

The Copy command's NONBUFIO argument can be used to override this setting on individual buttons, hotkeys, etc.

(Non-buffered mode is not supported on Windows XP, so you'll only see this option on newer versions of Windows.)

desc_show_info

For each file, the Description column normally shows:

• A metadata summary. (e.g. Picture type and dimensions, Audio codec and bitrate.)
• The user-defined description, if any. (This may be set via the Properties, Description command on the default toolbars. Some file types also allow user-defined descriptions/comments within their tags.)
• The target path, if the file is a shortcut or link.

This option lets you remove the user-defined descriptions and/or targets from the Description column. For example, if you have added the separate User description and Target columns then you may want only the metadata summary to be left in the Description column.

dlldir_security

This option, enabled by default, prevents Opus from loading DLLs from the current working directory. This reduces the risk of "binary planting" exploits which can trick your computer into running untrusted software when you open things like photos or music from folders in which someone has hidden a malicious DLL.

Turning this option off will reduce your security but may be needed if it causes problems with poorly written shell extensions or other third party software which is installed on your computer. (Such software is typically only tested with Windows Explorer, which does not traditionally used the more secure mode which Opus uses by default.)

This option only affects Opus and, potentially, the software you launch from Opus. It is not a system-wide setting (although there is one if you want to be even more secure; search the web for CWDIllegalInDllSearch for more information).

This option cannot be modified when running from a portable USB install.

dragdrop_async

When files are dropped on Opus from another program, Opus will usually handle them in the background so that its window remains responsive. If the program you dragged from supports the Windows API for asynchronous drag & drop then this should never be a problem; however, a large number of programs fail to support the API.

When dragdrop_async is on, Opus will attempt to handle all drops in the background, bending the rules if it has to, unless it detects a drop from a program known to have problems with this. If the option is off, Opus will be more strict and will only handle drops in the background for programs that explicitly support it.

If you run into problems when dragging files to Opus from certain programs, try turning this option off to see if it improves compatibility. The downside is that you may sometimes have to wait for drops to complete before you can continue using the window you dropped on.

file_size_units

Specifies the units to use when displaying file sizes and disk space. The traditional form is to use binary units (2^10-based) with "decimal" prefixes (1 KB = 1024 bytes). You can also choose to use decimal (10^3-based) units (1 KB = 1000 bytes) or binary units (1 KiB = 1024 bytes). See this Wikipedia page for more information.

find_unique_collections

Don't let simultaneous Find operations use the same collection for results. The Find function defaults to presenting its results in the Find Results File Collection. If you have two or more Find operations running in parallel, this option causes the name of the output File Collection for the second and subsequent tasks to be modified to be unique, so that the results are not intermingled.

ftp_copy_buffer_size

FTP copy buffer size (in bytes). This defines the size of the buffer used when transferring files via FTP. You should not normally need to change this.

ftp_do_not_cache

Normally the FTP system caches the directory listings of remote sites to improve performance. Turn this option on if you want to force remote directories to be refreshed every time you change folder on an FTP site.

ftp_no_pasv_change

If Opus detects a non-routable address has been specified as the result of a passive (PASV) FTP connection, it will try to correct this to the site's routable address. If you turn this option on then Opus will attempt to use the non-routable address as specified, which will only be successful if the FTP server is on the same network as the client machine. 

function_default_async

By default, a function that contains a single command will run asynchronously, and functions that contain two or more commands will run synchronously. This option lets you override this behaviour and make all functions (single or multiple commands) run asynchronously by default.

gloss_and_gradients

Enable gloss and gradient effects in various user interface elements. Turn this off if you prefer a flatter, more boring appearance.

group_column_maxwidth

Specifies the maximum width of the Group column. When file display columns are set to auto-size, this option prevents the Group column from growing larger than the specified number of pixels.

image_res_units

Units to use for columns relating to image resolution (Resolution (X), Resolution (Y)). If not set, each image file itself specifies the units, and so you may have a mix of inches and centimetres in any one directory - setting this option overrides the images and always displays consistent units.

layout_string

This option lets you define the name that is given to Lister Layouts that you drop on your desktop from the Layouts page in Preferences. You must specify a string that contains the code %1 - this code is replaced with the name of the layout in the generated shortcut. If nothing is specified for this option, the default is Layout '%1'.

max_md5_file_size

Specifies the maximum file size (in kilobytes) that Opus will calculate the MD5 or SHA-1 hash for when the MD5 Checksum or SHA-1 Checksum columns are displayed in a Lister. If a file is larger than this size its checksum can still be generated manually with the GetSizes MD5 or GetSizes SHA commands.

Special values:

• 0 - Ignore file sizes and always automatically calculate file hashes.
• 1 - Ignore file sizes and never automatically calculate file hashes.

max_thumbnail_size

The maximum pixel size (width and height) that Opus will generate thumbnails at. Larger thumbnails require more memory. This controls the maximum size thumbnail that be selected on the Thumbnails page in Preferences, and also via the Thumbnails Size slider.

mp3_custom_comments

The MP3 ID3v2 tag used for comments is not rigidly defined, and different third-party tools often use their own form of this tag. You can use this option to make Opus write COMM tags with the specified descriptions, to provide compatibility with these tools when using the Metadata pane. For example, MediaMonkey labels its COMM tag as Songs-DB_Custom1, so you would put this string into the mp3_custom_comments value to make Opus MP3 comments compatible with MediaMonkey. If you use multiple tools you can add multiple comment descriptions, one on each line, and Opus will write a separate COMM tag for each.

multipart_extensions

A "multipart file extension" is a file extension that consists of more than one part separated by dots. For example, in the Unix world .tar.gz files are quite common. In many cases (renaming, sorting, etc.) it makes sense to treat this whole string as the file extension, rather than simply .gz as is standard on Windows. Opus does this automatically for several archive formats, and the multipart_extensions option lets you add your own custom extension as well. Enter one extension per line.

network_errors

Yes

Specify error codes that indicate network authentication errors. Some network filesystems return undocumented error codes in the case of a username/password authentication error - if you are finding that you simply get an error dialog when attempting to connect to a network drive, you should note the error code and add it to this option. When Opus receives that error code it will treat it as an authentication failure and prompt you for credentials to access the resource. You can specify multiple error codes by separating them with semi-colons (e.g. 50;1003;1245).

no_contextmenu_fix

When the "Office 2003" style is selected for toolbars, Opus has to perform some magic to make owner-draw third party context menu extensions look good. If you find that Opus' magic isn't quite up to par, you can disable it with this option.

no_copy_dir_dates

Disable copying of folder timestamps. Timestamps will only be preserved for files when copying; folders that are created as part of a copy operation will have the current time and date.

no_folder_cd_thumbs

Disable automatic rendering of CD album thumbnails. If Opus detects that a folder contains mostly music files, and a thumbnail has been provided for the folder, it will normally render the thumbnail as if it were a CD cover. If you set this option this automatic behaviour is disabled, although you can still force a folder to appear as a CD cover in thumbnails mode by placing in it a file called coverart.jpg (or an alternate filename specified by the cd_thumb_coverart_file option).

open_container_in_tabs

This option is only used in File Collections, when you right-click with more than one item selected, and the items come from multiple virtual filesystems. In that instance only, Opus shows a cut-down context menu with two hard-coded entries at the top of it, one of which is an Open Containing Folder command. This option causes that command to open the items' containing folders in new tabs. Note that in all other cases, the commands displayed at the top of the context menu for collection items are configured through the File Types system.

progress_smoothing

Smooth progress bar updates on Vista and above. Turn off for lag-free progress bars which jump immediately when updated.

remember_net_paths

Opus normally remembers the previous path used in a system File Open or Save dialog (for example, when you use the Preferences Backup or Restore function), but for performance reason it does not remember network paths. Turn this option on if you want Opus to remember network paths as well.

setwallpaper_file

The Properties SETWALLPAPER command can be used to set a selected image file as the desktop wallpaper. By default the selected file is copied to your documents folder, but you can override the location by specifying a full path and filename for this option. The filename specified must end in either .bmp or (in Vista and above) .jpg.

show_release_history

When turned on, the Release History page in the help file will open automatically the first time Directory Opus is used after installing a new version. This helps you learn about new features, fixes and other changes in the new version. Turn the option off to prevent the release history page from appearing automatically.

styles_update_previous

If you have made changes to a Lister's appearance (by either opening or closing user interface elements manually, or via a Lister Style), the Prefs STYLE command lets you return the Lister to its initial appearance. If you turn this option on then what is considered to be the "previous" style is updated whenever a new Lister Style is chosen (and so Prefs STYLE=^prev would from then on reset the Lister to that style rather than its initial layout).

thumb_48x48_icons

Enables the use of 48x48 icons for thumbnails and tiles. This has trade-offs:

• If the setting is off, icons which have neither 256x256 nor 32x32 versions will look bad.
• If the setting is on, icons which have neither 256x256 nor 48x48 versions will look bad.

32x32 icons are far more common than 48x48 icons, so the setting is off by default.

(The exact icon sizes vary with system DPI settings. The sizes used here are for the standard DPI.)

Each icon can contain various versions of itself in different sizes. Regardless of this setting, Opus always prefers the high-quality 256x256 versions of icons which have them. For icons which do not have 256x256 versions, Opus requests a 32x32 version if the setting is off and a 48x48 version if the setting is on.

When an icon contains neither of the requested sizes, one of its other sizes is selected and scaled to fit. This is done by Windows itself and the scaling is not done to a high quality, with resized icons becoming blurry and messy. Windows will not say which sizes of an icon are available without scaling and will not indicate when an icon had to be scaled to fit a requested size, so the quality of the result is determined by the requested size and some icons will look bad either way.

(This option affects the icons for things like .EXE files. It does not affect actual .ICO files because Opus is able to generate thumbnails for them without these problems and compromises.)

tiff_max_doc_metadata

Maximum size (in megabytes) of TIFF images that Opus will attempt to extract document metadata from. This prevents problems with very large TIFFs, for example those saved by Photoshop.

wheel_acceleration

Opus normally applies a small amount of acceleration when scrolling in file displays using the mouse wheel, but you can disable it using this option if desired.

zip_dblclk_cache_time

Time (in minutes) to cache double-clicked files from within ZIP files. When you double-click a file to open it from a ZIP file, Opus extracts the file (and possibly others, subject to the Auto-extract options on the Archive Options Preferences page), and saves it to a temporary folder. If you double-click the same file again within the specified time, the already-extracted file will be used to save extracting the file again. This is set to 0 by default, meaning files are not automatically cached for double-click.