I kept getting these errors when I would log into my older idrac 6 cards. You can fixing it by putting IE11 into compatability mode, but I also found it easier to update the idrac to the latest 2.91 version. These were the errors I was getting:
I updated one as far back as 1.43 to this version, no middle version required. Enjoy! I pulled these files right off of dells website. The only file you need to upload is the firming.d6. It was taken out of the ESM_Firmware_MXKG2_WN32_2.91_A00.EXE.
Dell iDRAC Monolithic Release 2.91
http://vivithemage.com/extra/Dell-11G/firmimg.d6
If you want to use the virutal console, you will probably have to switch from native to JAVA, as native was not working for me in my old firefox version, or IE11, even with compatibility enabled.