your command should probably look like this:
hashcat -a 3 -m 900 e:\testvmhash.txt -1 charsets/standard/Russian/ru_cp1251.hcchr ?d?1 --encoding-to=utf16le --encoding-from=cp1251
If that doesn't work, what's hashcat's output?
hashcat -a 3 -m 900 e:\testvmhash.txt -1 charsets/standard/Russian/ru_cp1251.hcchr ?d?1 --encoding-to=utf16le --encoding-from=cp1251
If that doesn't work, what's hashcat's output?