It’s just data

Common Feed Errors

An analysis of a week’s work of click-throughs on Feed Validator [help] links

MissingGuid (1726)
RSS has an identity crisis.
SAXError (653)
People are bozos.  They make all kinds of errors.
UndefinedElement (629)
Yes, it really is pubDate with a capital D.  And no, itunes:category can’t be placed at the item level.
UnexpectedContentType (536)
Why are WordPress feeds served as text/html?
EncodingMismatch (519)
XML on the Web Has FailedBuy the t-shirt.
InvalidRFC2822Date (461)
The single most error prone format on the planet.  Evar.
HttpError (303)
If I can’t get to it, I can’t validate it.  Capisce?
ObsoleteNamespace (235)
What?  Atom 1.0 has been out for a full three months now, and your free hosting provider hasn’t yet upgraded?  Try FeedBurner.
ImageLinkDoesntMatch (206)
I’m still not sure why this is a problem.
UnicodeError (171)
If all you are doing is strcpy’ing your html page into your feed, do us all a favor and add the following line at the top.
<?xml version="1.0" encoding="iso-8859-1"?>


DuplicateDescriptionSemantics (136)
InvalidFullLink (135)
If only xml had provided a standard way to declare the base for a given URI…
People don’t seem to want to reveal their email addresses.  Perhaps they should be told about Dublin Core?
NotHtml (120)
Silent Data Loss.
UnexpectedAttribute (105)
Yes, it really is spelled isPermaLink with a capital P and a capital L.
ContainsHTML (96)
Some people really want to put markup in their titles.
BadCharacters (85)
Generally this means that there are some evil quote characters smarting off again.
SecurityRisk (84)
Beware of the platypus.
MissingDescription (78)
Some people don’t seem to want to provide both a title and a description for their feed.
MissingAttribute (78)
If you are going to include an enclosure element, you might want to put the url in there too. I’m just saying…
ContainsRelRef (76)
People seem to want to put relative URI references in their descriptions too.
DuplicateValue (69)
What part of globally unique do you not understand?
MissingItunesElement (65)
If you are going to submit your podcasts to iTunes, you really should include a category, a language, and indicate whether or not the podcast is “explicit”.  Think of the children.
UndefinedNamedEntity (60)
I don’t care if XHTML defines them in their DTD, DTD’s have not been a part of RSS since the summer of 2000.
NotInANamespace (58)
RSS 2.0 does not permit extensions to define child elements unless those child elements are also in a namespace.