Which settings do you have configured in the Find window? The Find and Replace window opens even on my 14 year old PC with Windows 7 as well as with the much newer PC with Windows 11 23H2 immediately without a several seconds delay after startup of UltraEdit for Windows v2024.0.0.28. Is the Find and Replace window configured as floating window as used by me or as docked window on left or right side of the main application window? Double click on the title bar of the docked Find and Replace window to change to floating window on which opening does not require so much window updates as on using the docked window. It could be further helpful clearing from time to time all the histories including the find/replace string histories which can be each up to 250. There is at Advanced - Settings or Configuration - Toolbars / menus - Miscellaneous the button Clear history. I use that button at least once per month.

Notepad++ loads a file on open always completely into memory as far as I know from posts on webpages. If a large/huge file does not fit into available RAM, it cannot be opened by Notepad++. UltraEdit opens files by making first a copy of the opened file which makes the opened file still readable and writable by other applications while the file is opened in UltraEdit (as also possible on loading the file completely into memory). The usage of a temporary file is necessary also for the undo/redo feature. Then UltraEdit loads just a block from the temporary file of the opened file. UltraEdit must load other blocks from the file on scrolling many pages quickly. The advantage is that UltraEdit can open any file of any size on any computer independent on available free RAM.

Several features of UltraEdit are counterproductive on working on large files with dozens of MB or huge files with several GB as these features require reading the whole file. That is the reason for  Advanced - Settings or Configuration - File handling - Large files introduced with UltraEdit for Windows v2023.1. There can be configured the large file threshold value and which features of UltraEdit to disable automatically on opening a large file. This features are disabled only for the large file exceeding the threshold value. The features are still enabled for all other files opened in same UltraEdit session. I strongly recommend making use of these configuration settings and check all those features you don't need on opening a large file. See the power tip Large file text editor and viewer.

The document map should be closed on working with large files as it is of no help for such files. I hope I don't need to explain why the document map is of no use for working with large files and why this feature is counterproductive on working with large files.

The usage of the Classic theme makes the user interface much faster as most of the styling features of the other themes are not available at all with the Classic theme. The Classic theme can be even customized by a user for disabling even more stylish features like color fading which makes window refreshing a lot faster. I use a customized theme based on the Classic theme which has at top in the XML file manually opened once in UltraEdit <Look>ID_VIEW_APPLOOK_WIN_2000</Look> for using the fastest look with nearly all not necessary window styles disabled. See the forum topic Custom versus default layout: What is the reason for pixel differences? created in January 2018 and not updated since creation. See also: How to modify Windows Classic theme?

There are also configuration settings which can be changed on UltraEdit seems to be slow. Many of those settings are regarding to reducing file system accesses done in background by UltraEdit which make UltraEdit user interface slow on having network drives configured currently not accessible using a LAN (local area network) because of working at home instead of the office or triggering a scanning of files by the anti-malware process running in background. Please read all posts of forum topic UltraEdit is getting very slow on startup which contains all hints on how to make UltraEdit faster with some clicks in configuration.

Which user interface mode do you use?

1. ribbon mode
   • always fully visible or minimized by default
   • in standard mode or in compact mode
2. toolbar/menu mode with contemporary menus
3. toolrbar/menu mode with traditional menus

The ribbon mode is the slowest on window refreshing and takes in most modes more vertical space than the toolbar/menu modes with the toolbars good arranged at top. There are multiple toolbars available by default and not just the main toolbar visible by default on switching from ribbon mode to one of the two toolbar/menu modes. Toolbars can be also customized. I have just one custom toolbar with the commands I usually execute by using a pointing device (mouse, pointing stick) or which show me the status of features. As I execute nearly all commands by key, a single custom toolbar with not many symbols (commands) is all I need regularly. I switch the layout on working on a project where I need more toolbars.

Which file tabs (document windows) mode do you use – dockable (MDI – multi-document interface) or not dockable (SDI – single document interface)?

While open file tabs bar mode is used – single line - scrollable or single line - drop down file list list or multiline tabs?

UltraEdit is a very powerful text editor with tons of features and tons of possible user customizations to fit the personal needs of a user. It is well spent time making use of all the customizations for an efficient work with UltraEdit according to the tasks usually to do with UltraEdit and not using just the defaults and just 3 to 10% of the available features as many users do for most applications used by them.