Problem with Dynamically Allocated Storage

[KirbyLA]

Is there a way to change a Dynamically Allocated Storage drive to a Fixed Size drive? Even though my drive has a 100 GB virtual size and an actual size of just 19 GB, I keep getting messages telling me that my system is low on storage. I thought Dynamic Allocation was supposed to take care of this automatically but I'm finding it's a big problem on my system. My guest system is Windows XP on a Windows 7 host. The problem is most acute when I am using Outlook Express, my favorite for e-mail.

[loukingjr]

Please attach the actual error message and the vbox.log (compressed) for the guest.

[KirbyLA]

OK, see the attached.

[mpack]

Why would you think that switching to a fixed size VDI would fix this problem? It won't.

Post a screenshot showing the size of the guests C volume (not the drive), and the number of bytes currently used.

My guess: the C partition is substantially smaller than the 100G drive. Also, you didnt read the part in the user manual which explains what dynamic drives are (hint: they do not have a variable capacity).

[KirbyLA]

Ok, here's the screen shot you asked for. Do you need any other information?

[Martin]

How much disk space is left on your host C: drive?

[mpack]

Ok, here's the screen shot you asked for.

No, that is not the information I asked for. I didn't ask to see the VDI on the host, I asked you to show me the guest's C: volume, which (given this new information) I now anticipate will be 20GB in size, and almost full.

Another guess: you already resized this from an older 20GB fixed size drive, though you haven't so far felt the need to mention it.

[mpack]

How much disk space is left on your host C: drive?

The host drive isn't the issue. That would not cause the guest to issue a low disk space warning, and offer to delete files. If the host was low on space it would be VBox issuing the warning, then it would suspend the VM.

[KirbyLA]

Is this the screen shot you need? I was under the impression that Dynamically Allocated Storage means that VirtualBox automatically increases the size of the C drive when needed. Is that not correct? You are right, I have increased the size of the drive already. What do you suggest I do now?

[mpack]

Yes, that is the guest information I need. As you can clearly see, the guest's C: volume is 20GB, as predicted, occupying a small portion of a 100GB drive. What you need to do is use a partition manager to adjust the C partition to fill the drive. See FAQ: How to resize a virtual drive. You have already done step 1, you still need to do step 2.

And no, there has never been a version of XP that can handle variable capacity drives. Once a partitions' filesystem is laid down, only a partition management tool can change it. The function of dynamic drives is explained in the user manual, but briefly: "dynamic" refers to dynamic allocation of storage on the host, not dynamic allocation of capacity in the guest. It is the feature which allows VDI files to be substantially smaller than a simple disk image would be for the same capacity.