That should be due to a problem with both LTspice and Electric.
The problem with LTspice is that the raw file format has changed.
As evidence of that, there is the statement at [1]:
"Regarding the error with LTSpice XVII, as Joshua Jones pointed
out, the error is due to the new version of LTspice using UTF16
encoding for .RAW files."
The problem with Electric is that it hasn't been updated to read the new LTspice XVII RAW format. As you have probably seen, there is currently no experienced Java programmer for Electric which is needed for doing that [2].
As was mentioned in the past, the current workaround should be to open the RAW file directly with LTspice [3,4].
[1] https://www.mathworks.com/matlabcentral/fileexchange/23394-fast-import-of-compressed-binary-raw-files-created-with-ltspice-circuit-simulator