Using Ubuntu 12.04 with xfce disktop manager
unfortunately while I tried to use badblocks command from Terminal to check if my 1TB portable drive is affected during long trip ...
my mistake that I used the command with the wrong switch -w (badblocks - w /dev/sdb1) !!!!!!!!!!!!!!!!!!!!!

I found that my drive is appearing as (unknown) in disk utility I thought maybe partition table was damaged , so I searched every where for a utility to rebuild my corrupted partition table and giving me access to my 290GB of data in this drive , at this moment I found everyone saying the testdisk is the one for that job ...
result of using testdisk is an old partition with non related data , and it didn't recognize any of clue about the fresh missing partition
now I stopped in order not to over write any more data on the drive until I find powerful utility to search the disk media surface for files and reconstruct the missing partition table
just to make sure, I used Recuva file recovery utility to search the drive and it successfully found my files without names or any other properties (just numirci names and correct file extension) ...
The point here that I am unable to find a big storage to recover all my files in it from this drive, additionally I can't rename 307070 file after recovery !!!!
what I need is a mean to reconstruct my lost partition table to access all my files which is not over written yet in this media till now , and waiting to be accessed !!! just reconstruct the partition table probably ...
After endless continues hours of trials of all program I could reach, I found one program called (Partition Guru) which was able to reconstruct the partition table during file recovery process for my external HDD .... it started with surface scan of the hard disk , and based on good logic (by using any file data it encounter, along with any remnant partition / boot sectors during the scan) it was able to offer me all possibilities of partition structure including old deleted partitions , and of course my lost partition was on top of them without missing any info ...
The concept behind the success of this utility was clear ... using every thing it find with full scan and not only depend on backups / old / remnant partition / boot sectors ...
the missing trick yet, is although that Partition Guru was able to reconstruct the partition table and its contents of file system correctly , it didn't offer to write these findings to the same media , but instead offer it as a virtual disk to use for recovering files from the missing partition to another media ....
Is there any way that Testdest manage to reconstruct the missing partition table (single primary NTFS partition) , and provide normal access to all files which still untouched till now !

BTW: one of utilities I used at first was GetData Back NTFS which was my favorite since long time , and I was shocked that it didn't recognize my lost partition at all , and didn't list it between history list of old partitions found in that drive ... although that specific partition was not altered at all since damaged !!!
attached the testdest.log
best regards,
Khaled