Invalid, non-existent, or outdated title
MediaWiki:Apierror-linter-invalid-title/en
Invalid or non-existent stylesheet specified.
MediaWiki:Apiwarn-invalidxmlstylesheet/en
Error: Image is invalid or non-existent.
MediaWiki:Imagemap invalid image/en
Invalid username or IP address provided
MediaWiki:Guc-invalid-username/en
Invalid username
MediaWiki:Sudo-error-sudo-invaliduser/en
Invalid username
MediaWiki:Maintenance-deleteBatch-error-invalid/en
Invalid username!
MediaWiki:Maintenance-invalidname/en
Invalid username
MediaWiki:Special-shareachievement-invalid-username/en
Invalid username
MediaWiki:Bs-privacy-anonymization-api-invalid-username/en
Invalid username "$1".
MediaWiki:Changeauthor-invalid-username/en
Invalid username "$1".
MediaWiki:Apierror-invaliduser/en
Invalid new username.
MediaWiki:Usermerge-badnewuser/en
Invalid argument for $1: < -1 or > 1.
MediaWiki:Pfunc expr invalid argument/en
The username is invalid.
MediaWiki:Bs-usermanager-invalid-uname/en
Contact username for access problems or queries:
MediaWiki:Privatedomains-emailadminlabel/en
UserName or 1.1.1.1
MediaWiki:Checkuser-investigate-targets-placeholder/en
Missing or invalid title.
MediaWiki:Twocolconflict-special-malformed-title/en
The username "$1" is invalid.
MediaWiki:Reassignedits-error-invalid/en
IP address or username:
MediaWiki:Sp-contributions-username/en
Username or IP address
MediaWiki:Guc-form-user/en
IP address or username:
MediaWiki:Regexblock-form-username/en
IP address or username:
MediaWiki:Checkuser-target/en
One or more values for parameter $1 are invalid.
MediaWiki:Validator list error invalid argument/en
Invalid or empty set name.
MediaWiki:Centralauth-editset-badname/en
Invalid username: "$3" (user ID $2)
MediaWiki:Maintenance-checkUsernames-error-notvalid/en