Just purchased new router Linksys E1200 and amazed I'm not able to update it in regular way using web-interface and official firmware from Linksys site. The update process fails at 10% and message 'Upgrade failed' appears.
Investigating the situation I have discovered the router exact model is Linksys E1200-RU with 2.3.00 firmware which was developed specially to Beeline Internet provider from Russia and its version is higher than newest FW published at official Linksys site. At the moment, 06/16/2017, the latest official E1200 firmware for HW versions 2 and 2.2 is 2.0.07 (build 5) from 07/13/2016.
As it follows from Linksys site the E1200-RU firmware ver. 2.3.00 release date is 10/01/2013, thus, it's pretty old and has well known security bugs.
Many of the Linksys E1200-RU owners report impossibility to replace the FW ver. 2.3.00 with ver. 2.0.07 or 3-rd party FW like DD-WRT. Moreover, release notes to ver. 2.3.00 firmware communicate incorrect information: "This firmware is only compatible with hardware version 2.3 (v2.3), but not with hardware version 1, 2 and 2.2". The last sentence isn't true as my E1200-RU router is regular HW ver. 2 E1200 router - there's no difference between E1200 and E1200-RU hardware. There exists difference in firmware only.
Thus, the russian router Linksys E1200-RU 2.3.00 FW and v.2.0 HW can be easily converted to regular Linksys E1200 v.2.0.07 FW.
First of all carefully check your router hardware version - look at the back of router to be sure your router is HW V2 router:
At the next step download official Linksys E1200 firmware: http://www.linksys.com/us/support-article?articleNum=148523 for 2.0 hardware version.
Open the downloaded firmware .bin file with your favorite HEX-editor. My HEX-editor is Bless under Linux Ubuntu. The file begins with 'E122':
Replace the 'E122' with 'E12R' and save changes:
Upgrade the router in regular way using the modified .bin file:
After the upgrade will be finished and router rebooted the router will be converted to regular Linksys E1200 v2 HW without any 'RU' and buggy 2.3.00 FW.
Use it as you want, apply future official Linksys upgrades or upgrade to DD-WRT and say bye-bye to Russia, which I hate sincerely.