|
| |||||||||
| Tags: disk management, primary partition, ubuntu, unallocated space, windows 7 |
![]() |
| | Thread Tools | Search this Thread |
|
#1
| |||
| |||
| Cannot create new primary partition - only 2 primary partitions on disk
I just tried to create a new primary partition using Disk Management. I get the error "You cannot create a new volume in this unallocated space because the disk already contains the maximum number of partitions." Ultimate goal is to create two more bootable partitions on my hard disk, one for Windows 7 and the other for Ubuntu. My C drive contains Windows Vista, my D drive has program files, and my E drive contains data. According to what I found online, you can have up to four primary partitions on a disk. According to DiskPart, this is what I have in terms of partitions: Partition ### Type Size Offset ------------- ---------------- ------- ------- Partition 1 OEM 10 GB 32 KB Partition 2 Primary 38 GB 10 GB - C drive Partition 0 Extended 10 GB 48 GB - D drive Partition 4 Logical 10 GB 48 GB Partition 3 Primary 61 GB 58 GB - E drive Any suggestions will be welcome thanks. |
|
#2
| |||
| |||
| Re: Cannot create new primary partition - only 2 primary partitions on disk
According to disk manager, you already have the max allowed. Only through the use of a third party utility like BootIT NG would you be able to get around this limitation. Leave the unallocated space as it is and allow setup for the other OS's to create the necessary installation volumes from the free space. In the case of Ubuntu, this will be necessary as Windows would not be able to create the necessary ext volumes. |
|
#3
| |||
| |||
|
As stated you already have the max amount of partitions for your drive. Four primary partitions are only possible if you dont have an extended partition. Could you not buy a second hard disk and then use that for your programs and Data. This will enable your Data to be accessible from all your operating systems as well as being safer. The extended partition IS a primary partition and counts as being one of the 4 primary partitions allowed. |
|
#4
| |||
| |||
| Re: Cannot create new primary partition - only 2 primary partitions on disk
Have you ever seen a Partition Table on a hard disk drive? Most users never have. It really is quite simple. Just 64 bytes on the first physical sector of a physical hard drive. It's not a file or part of a file because, at the point during startup when the not-yet-fully-awake system needs this information, it doesn't yet know how to deal with files or folders. The first physical sector on the disk holds just 512 bytes of code (same as every other sector on the disk). About 400 bytes of this represents the mysterious(?) MBR (Master Boot Record) that we've all heard about. And, starting at offset 01BE of that first sector, we find the Partition Table, which looks like this (copied from http://technet.microsoft.com/en-us/l...b457122.aspx): 000001B0: 80 01 .. 000001C0: 01 00 07 FE BF 09 3F 00 - 00 00 4B F5 7F 00 00 00 .?...K..... 000001D0: 81 0A 07 FE FF FF 8A F5 - 7F 00 3D 26 9C 00 00 00 ...........=&.... 000001E0: C1 FF 05 FE FF FF C7 1B - 1C 01 D6 96 92 00 00 00 ................. 000001F0: 00 00 00 00 00 00 00 00 - 00 00 00 00 00 00 ............... It would be more obvious that those are 4 rows of 16 bytes each if it didn't start near the end of each line (like a calendar for a month that starts on Friday). That first 16-byte entry is really: 80 01 01 00 07 FE BF 09 3F 00 - 00 00 4B F5 7F 00 The "80" says that this is an Active (bootable) partition. The next byte says this partition starts at Head 1. The next 2 bytes tell the starting sector and cylinder (using 6 bits and 10 bits, rather than 8 bits each). The next byte (07) says this partition uses an Installable file system: NTFS, most likely. If this byte is 05 (rather than 07), this partition is an "Extended Partition". The next bytes tell the starting and ending sectors and the size of the partition. That's all. The partition table doesn't have room to store any more info about the partition, and it doesn't have room for more than 4 entries. So, how do we get more than 4 partitions on one disk? We don't (unless we use a 3rd-party system, such as BootItNG). But if the 5th byte for one of the partitions is 0E, then there is an EBR (Extended boot record) somewhere else on the disk that can hold similar entries for one or more Logical Drives. (I've not been able to find and actually SEE and EBR on my hard drives, so you're on your own for exploring this subject further.) In your case, DiskPart says that you have 4 partitions already: Partition 1 (OEM), Partition 2 (Drive C:), Partition 3 (Extended) and Partition 4 (Drive E:). I suspect that you've misread the DiskPart entry for your Drive D:. Your Extended partition is NOT Drive D:. A drive letter is never assigned to an extended partition. Your Drive D: is the first (only) Logical drive IN the Extended Partition. Note that the Logical drive starts at offset 48 GB (from the beginning of the HDD), same as the beginning of the Extended Partition. You could easily create additional Drives F:, G:, X: and others within the Extended Partition (if your Drive D: were not already using all of the Extended Partition's 10 GB of space). None of those would require an entry in the disk's Partition Table; they would all be entries within the EBR. If you really want to understand these concepts, Vistanoob, find a copy of the Resource Kit for Windows Vista (or any other Windows version) and invest an afternoon in studying at least the "Troubleshooting Disks and File Systems" part. If you can't find the book (which has well over 1,000 pages and costs $50 or more), then read it online at the link I gave above. Several hours invested here will pay dividends, not just for this problem but for as long as you use computers - which may be the rest of your life. I'm grateful for the many hours I spent back in the 1980's with Norton Utilities, especially DiskEdit, which let me read my disks, byte by byte, and explained what those bytes meant. But I know nothing of Ubuntu or Linux or other operating systems. |
|
#5
| |||
| |||
| Re: Cannot create new primary partition - only 2 primary partitions on disk
Lots of good information here - thank you RC and all who replied. I may wind up 1. deleting partition E after a backup - it's just data, no program files 2. increasing the size of the extended partition on which drive D lives, and creating a new logical drive E there for my data 3. creating a new primary partition in the remaining unallocated space on which Windows 7 or Ubuntu could live. That would keep me to a total of four partitions. Any advice on step 2 - increasing the size of the extended partition on which drive D lives but keeping drive D to its present size? |
|
#6
| |||
| |||
| Re: Cannot create new primary partition - only 2 primary partitions on disk
Hi, Vistanoob. Your step 2 sounds like a good plan to me. ;<) One little gotcha that you probably already know about: When you Extend the partition, specify the space in MEGAbytes, not Gigabytes. The first TWO times that I Extended a volume, I put in "10" for a 10 GB extension - and the volume grew by the full 61 GB (in your case)! It seems that 10 MB was too small, so Extend used the default - which is ALL the available space. So put in 10,000 MB, not 10 GB. |
![]() |
|
| Thread Tools | Search this Thread |
| |
Similar Threads for: "Cannot create new primary partition - only 2 primary partitions on disk" | ||||
| Thread | Thread Starter | Forum | Replies | Last Post |
| How many partitions will you do in your Primary HDD | Quintessa | Polls & Voting | 6 | 2 Weeks Ago 07:22 PM |
| Migrate primary partition from single disk to RAID array | gatorIT | Small Business Server | 3 | 06-04-2009 05:12 PM |
| Moving Primary Partition | Quentin | Operating Systems | 5 | 06-11-2008 03:17 PM |
| Extend primary partition using Gparted | varunb | Vista Help | 3 | 14-08-2008 09:05 PM |
| Vista Ultimate changed Primary partitions to Dynamic and created hidden partition with the primary "partitions" listed as Volumes | craigv | Operating Systems | 2 | 03-06-2008 04:16 PM |