Please install “Uipath…Excel.Activits” Package from package manager.
You can use hot key “Ctrl+p” to call a package manager and from there you can installed this package and you will find after installing above package the write csv activity.
**Note- Always If you are a new user of uipath then before starting first installed all “Available packages” from package Manager. if you are using New uipath stable version then by using ctrl+p you will be able to open a package manager.
I’m having a similar issue. I can write a text file but when I try to write it as a CSV file it gives me the Object reference not set to an instance of an object. What am I doing wrong? I’m just trying to read a PDF and put it in a CSV file to process it with the UiPath studio process.