Downgraded xprog from 5.55 to 5.51 but getting error invalid certificate

[jyunes]

Hello, newbie here, as the title says, After a succesful downgrade to 5.51 firmware with usbasp programmer, Im getting the error "invalid certificate", I must say Im using xprog 5.55 software, will that be an issue? I don,t have xprog 5.51 only 5.55 since that is what the cd had.

Also, how can I set a profile pic?

thanks in advance!