Error in melt(spx_ftse_00_10, id = "Date") : could not find function "melt"

Hi Ahmed,
thanks for reaching out! You should make sure you have the necessary packages installed for this lesson, which are:
reshape2
plyr
You can use

install.packages("NameofPackage")

directly in your console to install the required packages. Also, you only need to do this once, after that the packages should be installed and ready to use and you can access them with the following line in your script:

library("NameofLibrary")

Best,
365 Eli