There could be sitiuations when you are importing data into Web TimeSheet using CSV files.
-CSV files can be manually created or data can be imported from a third party application.
-When you create the CSV file in a text editor and if there are fields which contain commas, since comma is a seperator it will put the data into two columns.  
That is if you are trying to import "830, 910 – 7th Avenue", "SW 830" will be put into one column and the rest "910 – 7th Avenue SW 830" will be put into a seperate column. 
The result is that the import utility or the CSV import will throw an error that the task is invalid and it will not allow us to import the task.  Check the "Comma in field name.PNG" attached to the solution.
If a field value contains commas, you must put the entire value in quotations (e.g., "830, 910 – 7th Avenue SW").
Please Note:
This issue will not showup if you are using 'Excel' to setup the CSV file as Excel will put the double quotations automatically when there is a comma in the field name.