When using a browser, connect to PExx08 series PDU can not login the error message is Login fail.  

To solve this issue, please use the WEB browser (Firefox Portable V.107.0) attached with this FAQ to upgrade the PExx08 firmware to V2.4.239 or higher.

You can also download for below web site:

https://sourceforge.net/projects/portableapps/files/Mozilla%20Firefox%2C%20Portable%20Ed./Mozilla%20Firefox%2C%20Portable%20Edition%20107.0/

To upgrade the firmware, please download the firmware and manual from 

https://www.aten.com/global/en/supportcenter/downloads/?q=PE6208

Please check the manual for how to upgrade firmware. 

If you still have problems, please contact ATEN Tech Support

https://eservice.aten.com/eServiceCx/Common/FAQ/askQuestion.do?type=None