You create a certificate request and submit it to your internal CA and you get this error.
“Error Parsing Request The request subject name is invalid or too long”
It may seem odd, as the CN for your request isn’t that long.
Tip. Check the country field, this only supports the two characters
certutil -dump %YourRequestFile%
It is discussed in futher detail in this forum post.
If you prefer openssl, us this command
openssl req -noout -text -in %YourRequestFile%