How to know what is the correct update firmware?

I have a htc m7 in 4.3, and i want to update to lolipop.
Already try:
RUU_M7_WL_L50_SENSE60_SPCS_MR_Sprint_WWE_6.23.651. 6_Radio_1.01.20.1225_CNV_CNV_SPCS_4.38_003_release _425282_signed_2
RUU_M7_UL_L50_SENSE60_MR_BrightstarUS_WWE_7.17.154 0.7_Radio_4T.35.3218.16_10.33Q.1718.01L_release_42 0191_signed_2
RUU_M7_WL_L50_SENSE60_SPCS_MR_Sprint_WWE_6.23.651. 7_Radio_1.01.20.1225_CNV_CNV_SPCS_4.38_003_release _446375_signed_2

When the process begins always get the error:

error 155 unkown error
obtain the correct update utility and try again

How to know what is the correct version?