IDM has been fighting trial resets since version 5.0. With each update, they introduce new registry keys and fingerprinting mechanisms (like storing installation time in multiple encoded locations). The J2Team developers have noted that IDM 6.43 beta includes a new that may eventually render simple registry resets useless.

the trial using the Registry Editor instead of a third-party tool? Releases · J2TEAM/idm-trial-reset - GitHub

372DC10FBE87C1744D2852877E0D36D37E034B5507F868DE61C8BA6A46D0E012 : Extract the ZIP file and run the IDM Trial Reset.exe with administrative privileges. Reset the IDM trial now