Limitations on File Content
BlazeMeter cannot read files containing non-ASCII characters. You must remove all non-ASCII characters from your files before uploading and starting a test.
Restriction: Exceptions: ZIP files (but not the files they contain) and JAR files.
Use the following regex,
[^\x{00}-\x{80}]
, to find all non-ASCII characters and be sure to remove ALL traces from your script, including disabled functions.