Some of the sufi websites (http://www.sunnah.org and http://www.haqqaninaqshbandiuk.com and many others) have quoted the following statement by Imam ad-Daraqutni from the book of Ibn al Jawzi Sifat al Safwah.
Abu al-Hasan al-Daraqutni said: "We used to seek blessings from Abu al-Fath al-Qawasi's grave." 2:471.
see the screen shots
When we see the book by Imam Ibn al Jawzi the word "grave" is not even mentioned rather it states:
قال أبو الحسن الدارقطنى كنا نتبرك بأبي الفتح القواس وهو صبي
ہم ابو الفتح سے اس وقت تبرک حاصل کرتے تھے جبکہ وہ بچہ تھا !
Abu al Hasan Darqutni said we used to seek blessings from Abul Fath al Qawwaas while he was a boy (or child). [Sifat al Safwah Page 471]
Comment: This is clear that Imam ad-Daraqutni believed that tabarruk can not be sought after the death of the Auliyah as he said: "WE USED TO SEEK BLESSINGS". So, this saying is against sufis and Imam Khateeb Baghdadi quoted this saying with his chain in Tareekh Baghdad vol 14 page 328 which is authenticated by Shaykh Rafiq Taahir.
Note: In the life of a pious people one can take blessings from him as it is mentioned in the hadeeth
Whenever Allah's Messenger (ﷺ) became sick, he would recite Mu'awwidhat (Surat Al-Falaq and Surat An- Nas) and then blow his breath over his body. When he became seriously ill, I used to recite (these two Suras) and rub his hands over his body hoping for its blessings. [Sahih al-Bukhari 5016]
Some of the fatawa by the scholars of Ahlus sunnah
a) Shaykh Ibn Uthaymeen said "Seeking blessing from righteous people is of two types.
1 – Seeking blessings by asking them to make du'aa' to Allaah for one. This is permissible, subject to the condition that they be known to be righteous and pious and that they will not be exposed to fitnah thereby.
2 – Seeking blessing through their relics, such as their clothes and belongings, etc. This is not permissible and is a form of reprehensible bid'ah (innovation).(Islam QA fatwa no: 26284)
Regarding second type of Tabarruk there is a fatwa by Imam Abu Ishaq al-Shaatibi
b) Imam Abu Ishaq al-Shaatibi said:
الصحابة -رضي الله عنهم- بعد موته - عليه الصلاة والسلام- لم يقع من أحدٍ منهم شيء من ذلك بالنسبة إلى من خلفه، إذ لم يترك النبي -صلى الله عليه وسلم - بعده في الأمة أفضل من أبي بكر الصديق -رضي الله عنه- ، فهو كان خليفته، ولم يُفعل به شيءٌ من ذلك، ولا عمر - رضي الله عنه-، وهو كان أفضل الأمة بعده، ثم كذلك عثمان، ثم علي، ثم سائر الصحابة الذين لا أحد أفضل منهم في الأمة، ثم لم يثبت لواحد منهم من طريق صحيح معروف أن متبركاً تبرك به على أحد تلك الوجوه أو نحوها، بل اقتصروا فيهم على الاقتداء بالأفعال والأقوال والسير التي اتبعوا فيها النبي -صلى الله عليه وسلم- فهو إذاً إجماع منهم على ترك تلك الأشياء.
After the death of the Prophet (peace and blessings of Allaah be upon him), none of the Sahaabah (may Allaah be pleased with them) did anything of that nature with regard to those who succeeded him as leaders. The Prophet (peace and blessings of Allaah be upon him) did not leave behind in the ummah anyone who was better than Abu Bakr al-Siddeeq (may Allaah be pleased with him), who was his successor, and he did not do anything of that sort, and neither did 'Umar (may Allaah be pleased with him), and they were the best of the ummah after him. Neither did 'Uthmaan, or 'Ali, or any of the Sahaabah, and there is no one in the ummah who is better than them. There is no report from any of them via any sound isnaad that they sought blessings in any of these ways or similar ways. Rather they limited themselves to emulating the actions, words and conduct of the Prophet (peace and blessings of Allaah be upon him). So there is consensus among them that all such things should be avoided. [Al Aitesa'am Vol 1 page 286,287]
Following is the translation of an Article by Abu Abdullah Saarim which was published in Majallah as-Sunnah no. 35 page 13 of Shaykh Ghulam Mustafa Zaheer.
"Some people have started a false aqeedah against Qurah, Hadeeth, Muhadditheen and the Taaifah al Mansoorah that Prophet peace be upon him is Haadir Naadir (Omnipresent). See the short evidences of ahadeeth against this false and extremely deviant aqeedah.
1. Aisha reported
فَقَدْتُ رَسُولَ اللَّهِ صلى الله عليه وسلم لَيْلَةً مِنَ الْفِرَاشِ فَالْتَمَسْتُهُ
One night I missed Allah's Messenger (peace be upon him) from the bed. [Sahih Muslim no. 486]
3. Abdullah Ibn Masood said
كُنَّا مَعَ رَسُولِ اللَّهِ صلى الله عليه وسلم ذَاتَ لَيْلَةٍ فَفَقَدْنَاهُ فَالْتَمَسْنَاهُ فِي الأَوْدِيَةِ وَالشِّعَابِ فَقُلْنَا اسْتُطِيرَ أَوِ اغْتِيلَ - قَالَ - فَبِتْنَا بِشَرِّ لَيْلَةٍ بَاتَ بِهَا قَوْمٌ
we were in the company of the Messenger of Allah (peace be upon him) one night and we missed him. We searched for him in the valleys and the hills and said. He has either been taken away (by jinn) or has been secretly killed. He (the narrator) said. We spent the worst night which people could ever spend. When it was dawn we saw him coming from the side of (the cave of) Hira'. He (the narrator) reported. We said: Messenger of Allah, we missed you and searched for you, but we could not find you and we spent the worst night which people could ever spend. [Sahih Muslim no. 450]
4. Aisha said:
افْتَقَدْتُ النَّبِيَّ صلى الله عليه وسلم ذَاتَ لَيْلَةٍ فَظَنَنْتُ أَنَّهُ ذَهَبَ إِلَى بَعْضِ نِسَائِهِ فَتَحَسَّسْتُ ثُمَّ رَجَعْتُ فَإِذَا هُوَ رَاكِعٌ أَوْ سَاجِدٌ يَقُولُ " سُبْحَانَكَ وَبِحَمْدِكَ لاَ إِلَهَ إِلاَّ أَنْتَ "
I missed one night the Messenger of Allah (peace be upon him) (from his bed). I thought that he might have gone to one of his other wives. I searched for him and then came back and (found him) in a state of bowing, or prostration, saying: Hallowed be Thou and with Thy praise; there is no god but Thou. [Sahih Muslim no. 485]
5. Abu Huraaira said:
أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم فَقَدَ نَاسًا فِي بَعْضِ الصَّلَوَاتِ
The Messenger of Allah (peace be upon him) found some people absenting from certain prayers.