Error En Validación W3C

[gloomy]

He intentado validar la página web que tenemos creada con prestashop: pero ha sido imposible y me avisa de un varios errores:

8 Errors, 31 warning(s)

 

Line 123, Column 14: character "&" is the first character of a delimiter but occurred as data

if (data && (data > 0)) {

 

This message may appear in several cases:

• You tried to include the "<" character in your page: you should escape it as "<"
  
• You used an unescaped ampersand "&": this may be valid in some contexts, but it is recommended to use "&", which is always safe.
  
• Another possibility is that you forgot to close quotes in a previous tag.
  

el siguiente error es:

 

• Line 135, Column 9: multiple comments in comment declaration
  <!---------------- Analytics--------------------------------------------…
  

los demas son mas de lo mismo

 

Alguien le ocurrio lo mismo??