Hi thanks for your answer. I do not think that the drive originally had any partitions. It is my backup drive and I only keep backups in it. I reformatted it (now and lots of other times in the past (so I should have noticed a partition), but it did not help. It all came about, when I installed the Acronis Recovery Manager. It created a Secret Zone. I did not like this, because it took away my backup space. I read in Acronis help, that if one deletes Acronis 2009, a wizard comes up, which asks whether I want to delete the Secret Zone. I did this. However, the Secret Zone became unallocated space (I should have clicked on: distribute SZ). It is Drive H (Simple, Basic, NTFS, Healthy (ACtive, Primary Partition, Cap. 289.20 GB), unallocated 176 GB). So it looks like a Partition now. How to I reinstall it, after I have made it all unallocated. Do I really need a Partition?
(My other drive is C 465 MB, Simple, Basic, NTFS, (System, Boot, Page File), Active Primary Partition).