I have search internet and these forums, so if this has been answered already I apologize for asking again. Phone is currently running 1.0.6.9. I have tried every method … http, https, tftp and the links from grandstream firmware page.
Any help would be greatly appreciated.
Hi,
You need to first upgrade to middle ware firmware 1.0.7.xx and it is mentioned on firmware page.
firmware.grandstream.com/gxp21xx/1_0_7_97
firmware.grandstream.com/gxp21xx/1_0_8_56
firmware.grandstream.com/gxp21xx/1_0_9_135
After that you can upgrade latest version. Please read release note for better understanding.