I have restarted my computer after an update, then I have noticed that the wifi signal was very weak. I have decided to download this package https://github.com/lwfinger/rtlwifi_new and reinstall the wifi driver but I have the following error: modprobe: ERROR: could not insert 'rtl8723be': Exec format error

I run the following in the package downloaded:

sudo make install
modinfo -p rtl8723be

I have following result :

swenc:Set to 1 for software crypto (default 0)
ips:Set to 0 to not use link power save (default 1)
swlps:Set to 1 to use SW control power save (default 0)
fwlps:Set to 1 to use FW control power save (default 1)
msi:Set to 1 to use MSI interrupts mode (default 0)
debug:Set debug level (0-5) (default 0) (int)
disable_watchdog:Set to 1 to disable the watchdog (default 0)
ant_sel:Set to 1 or 2 to force antenna number (default 0)


sudo modprobe -r rtl8723be

sudo modprobe rtl8723be ant_sel=1

I have following result :

modprobe: ERROR: could not insert 'rtl8723be': Exec format error

I have tried to restart the adapter with the following command:

sudo service networking restart

I'm using ubuntu 17.04 | 4.10.0-33-generic

  • You don't need to install anything for 17.04. Uninstall the custom module.
    – Pilot6
    Aug 29, 2017 at 9:48
  • @Pilot6 , If I run the following command sudo apt-get install --reinstall rtlwifi_new-master linux-firmware in the folder of the downloaded package , I have this error : E: Unable to locate package rtlwifi_new-master
    – Sirius
    Aug 29, 2017 at 9:57
  • This command could not output anything else. There is no rtlwifi_new-master package. You need to uninstall what you installed from git. You need to run sudo make uninstall from the directory with the source.
    – Pilot6
    Aug 29, 2017 at 10:05
  • @Pilot6, I just uninstall the package , but my wifi adapter still not detected .
    – Sirius
    Aug 29, 2017 at 10:43
  • 2
    @Pilot6, I fix my issue by following the step in this answer: rlt8723be. Thank so much for your help :)
    – Sirius
    Aug 29, 2017 at 11:12

4 Answers 4


I had the same problem, i used to run make, install, mod....etc commands from the same old directory "rtlwifi_new"(which i downloaded a month ago) .

Try a fresh installation by downloading all files again.


if you have rtlwifi_new downloaded,

cd rtlwifi_new
sudo make uninstall
sudo make clean

Then, make, install and insert the module. Don't re-download the repo.


Same as @Pilot6 (thanks!!!), I fixed my issue with: Wifi problems with rtl8723be in Ubuntu 14.04

After every kernel update:

  1. Execute

     cd rtlwifi_new
  2. Clean previous builds with

     make clean
  3. Update git repository with

     git pull
  4. Compile it with

     make clean && make
  5. And install with

     sudo make install
  6. Reboot or unload/load modules.


Navigate to the modprobe.d folder in root>>etc using terminal and remove the rtl8723de.conf if it exists.Use

sudo rm rtl8723de.conf

It worked for me, try a fresh installation of the wifi driver. You can clone the repository again and start again if you face problem in installation.

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