Sending an alert mail via a workflow - sharepoint-2010

Question

I am currently doing support on a SharePoint 2010 intranet.
A functionality has been implemented in a site allowing users to make holiday requests.
A user must fill in an InfoPath form to make an holiday request.
A record is added to a library when an holiday request is made.
And then a workflow is started.
One of the first action in the workflow is sending a mail to the requester's manager for validation.
Then the workflow waits until the manager's validation.
The client would like an alert mail to be sent automatically to the manager when he has not validated/refused a request after a certain number of days.
My first idea was to implement a program using the SharePoint object model and to execute the program as a Windows scheduled task.
But I am a workflow beginner and I am wondering whether it is possible to satisfy my client's need with worflow features.
Any help will be greatly appreciated.

Answer 1

Start a parallel execution - type parallel, it'll give you two blocks which will execute in parallel.
In one of the blocks, you wait for the approval.
In the other, you pause until a given date (suggestion: create a new date variable, set it to today, then add the necessary amount of dates). After that pause, send the reminder email.
Alternative solution:
You could also read about retention stages. If you're saving the date that email was sent in a list item, you could have the information management policy to run a timer job... Said job will start another workflow after a given amount of days has passed since the first email was sent. In this workflow you could send the reminder email.

Answer 2

My experience regarding SharePoint workflows is that you do want to avoid using pauses because sometimes they never unpause (for example, take a look at this). Instead, you're going to want to set up a timer job which operates daily, checks the date variable that Rehan mentioned, and sends an email if today's date equals the date you want to send the email (if this is based on a task, you could just use the create date):
DateTime createdDate = (DateTime)item["Created"];
string createdPlus7 = createdDate.AddDays(7).ToShortDateString();
string createdPlus14 = createdDate.AddDays(14).ToShortDateString();
if(DateTime.Today.ToShortDateString() == createdPlus7)
{
Send7DayEmail();
} else if(DateTime.ToShortDateString() == createdPlus14)
{
Send14DayEmail();
}
That's probably too much casting and recasting but it should give you a start.