Salaam everyone,
I just wanted to share an experience with all of you so that you are aware of the procedures.
My husband sent his passport through TCS courier yesterday with all the required documents. Today the courier individual, upon reaching the gates of Islamabad Visa Office called my husband and had him speak to the security person at the gates of the office. The individual told my husband that they don't accept any passports through TCS and that my husband will have to come there personally to drop it off. I have never heard of this before. I thought dropping it off personally and sending through mail are 2 options we have. So anyways, my husband called the Islamabad visa office later to verify this and indeed the Islamabad visa office agent told my husband that they don't accept passports through TCS or any mail delivery method for that matter. My husband also verified some general information. So, tomorrow (assuming he will get the package back from TCS early tomorrow) my husband will go to the Lahore visa office as that is closest to him. The Islamabad visa office agent said that he can take the passport to any of the 3 locations they have (Lahore, Islamabad or Karachi) and drop it off. He'll get it back in about 1-1.5 weeks.
So before sending the passport through any mail services, please call the embassy which you are planning to send the passport to, and verify if this is an acceptable method. We got PPR last Thursday but didn't submit the passport until yesterday because of Muharram holidays and now another day got wasted.
Hope this helps!