Running 'package-install-file' on a tar file might throw a 'Wrong type argument: arrayp, nil' error from 'tar--check-descriptor’.  The problem comes from assumptions made by 'package--description-file' and tar-mode about the filenames contained in the tar file.  I’ve written a detailed description of the error and root cause here . I propose adding a 'condition-case' to 'package-install-file' to return a friendly message. diff --git a/lisp/emacs-lisp/package.el b/lisp/emacs-lisp/package.el index 82fcf439a11..01f659e6982 100644 --- a/lisp/emacs-lisp/package.el +++ b/lisp/emacs-lisp/package.el @@ -2439,8 +2439,10 @@ directory."        (insert-file-contents-literally file)        (set-visited-file-name file)        (set-buffer-modified-p nil) -      (when (string-match "\\.tar\\'" file) (tar-mode))) -    (package-install-from-buffer))) +      (when (string-match "\\.tar\\'" file) (tar-mode) +            (condition-case nil +                (package-install-from-buffer) +      (error (message "%s is not a valid package file" (file-name-nondirectory file))))))))   ;;;###autoload  (defun package-install-selected-packages (&optional noconfirm) In GNU Emacs 30.1 (build 1, aarch64-apple-darwin21.6.0, NS  appkit-2113.65 Version 12.7.6 (Build 21H1320)) of 2025-02-24 built on  armbob.lan Windowing system distributor 'Apple', version 10.3.2575 System Description:  macOS 15.5 Configured using:  'configure --with-ns '--enable-locallisppath=/Library/Application  Support/Emacs/${version}/site-lisp:/Library/Application  Support/Emacs/site-lisp' --with-modules 'CFLAGS=-DFD_SETSIZE=10000  -DDARWIN_UNLIMITED_SELECT' --with-x-toolkit=no' Configured features: ACL GLIB GMP GNUTLS JPEG LIBXML2 MODULES NOTIFY KQUEUE NS PDUMPER PNG RSVG SQLITE3 THREADS TIFF TOOLKIT_SCROLL_BARS TREE_SITTER WEBP XIM ZLIB Important settings:   value of $LANG: en_US.UTF-8   locale-coding-system: utf-8-unix Major mode: Lisp Interaction Minor modes in effect:   tooltip-mode: t   global-eldoc-mode: t   eldoc-mode: t   show-paren-mode: t   electric-indent-mode: t   mouse-wheel-mode: t   tool-bar-mode: t   menu-bar-mode: t   file-name-shadow-mode: t   global-font-lock-mode: t   font-lock-mode: t   blink-cursor-mode: t   minibuffer-regexp-mode: t   line-number-mode: t   indent-tabs-mode: t   transient-mark-mode: t   auto-composition-mode: t   auto-encryption-mode: t   auto-compression-mode: t Load-path shadows: None found. Features: (shadow sort mail-extr emacsbug message mailcap yank-media puny dired dired-loaddefs rfc822 mml mml-sec password-cache epa derived epg rfc6068 epg-config gnus-util text-property-search time-date subr-x mm-decode mm-bodies mm-encode mail-parse rfc2231 mailabbrev gmm-utils mailheader cl-loaddefs cl-lib sendmail rfc2047 rfc2045 ietf-drums mm-util mail-prsvr mail-utils rmc iso-transl tooltip cconv eldoc paren electric uniquify ediff-hook vc-hooks lisp-float-type elisp-mode mwheel term/ns-win ns-win ucs-normalize mule-util term/common-win tool-bar dnd fontset image regexp-opt fringe tabulated-list replace newcomment text-mode lisp-mode prog-mode register page tab-bar menu-bar rfn-eshadow isearch easymenu timer select scroll-bar mouse jit-lock font-lock syntax font-core term/tty-colors frame minibuffer nadvice seq simple cl-generic indonesian philippine cham georgian utf-8-lang misc-lang vietnamese tibetan thai tai-viet lao korean japanese eucjp-ms cp51932 hebrew greek romanian slovak czech european ethiopic indian cyrillic chinese composite emoji-zwj charscript charprop case-table epa-hook jka-cmpr-hook help abbrev obarray oclosure cl-preloaded button loaddefs theme-loaddefs faces cus-face macroexp files window text-properties overlay sha1 md5 base64 format env code-pages mule custom widget keymap hashtable-print-readable backquote threads kqueue cocoa ns multi-tty make-network-process emacs) Memory information: ((conses 16 39125 8959) (symbols 48 5269 0) (strings 32 12063 2290)  (string-bytes 1 290705) (vectors 16 9393)  (vector-slots 8 106790 6658) (floats 8 21 8) (intervals 56 253 5)  (buffers 992 11))