how I said already: it worked all the time. I didn’t change the configuration.
BC Differ is set as search engine.
I get a file selection for comparing and that was all. The source file for compare stays visible and the selected file is not visible and the editor works normal as editor.
Can you verify BCDiffer.dll is in Multi-Edit’s install directory and its size is 1846kb?
If that is ok, in Tools-Customize-File Compare, select Multi-Edit FC, run a compare then switch it back to BCDiffer and try a compare.
If it is still not working use the following post to locate your config directory. viewtopic.php?t=2013
Then, with Multi-Edit (ME) not running rename MeConfig.db to MeConfigbk.db, and Wcmdmap.db to Wcmdmapbk.db then restart ME and see if BCDiffer is working.
If it is still not running, you will need to do a reinstall. You can save the two files you renamed and then after a reinstall rename them back to the original names in the config directory to restore and customizations you did to ME.