Error connecting to the LDAP server: Failed to parse DN

I am getting the following error when testing LDAP settings with some user accounts but not others. I have updated to Spring-LDAP-1.3.0.RELEASE but it did not help.

Error connecting to the LDAP server: Failed to parse DN; nested exception is org.springframework.ldap.core.ParseException: Encountered "\"" at line 1, column 1.
Was expecting one of:
...
...
" " ...