"The disk is write protected" error on a Windows Failover Cluster Node VM

Lately, I came across this issue where database team was unable to start the sql service on SQL cluster nodes and when they checked SQL logs, found the drive where temp database stored was no more writable (I have seen this issue a few times in past and if I remember correctly every time this happened on Windows Server 2008 R2 server failover cluster nodes) .

When tried to create a new object in this drive, found no option to do so and checking the disk for errors from disk properties => Tools, end up with an error like,

I am not sure what caused this issue however, found following Volume Shadow Copy service error entries in event viewer, “A critical dynamic disk is a virtual hard disk. This is an unsupported configuration.” So, suspect this has something to do with volume shadow copy and Microsoft server cluster.

We can fix this Write protected disk issue by clearing the read only attribute from volume level (in my case clearing the read only attribute from disk didn’t work so suggest you clear the attribute at lowest level).

To do so follow these steps:

First open disk management and note down the disk and volume name/number of affected drive/volume.

1. Open a command prompt, type in Diskpart and then press Enter.
2. Run the command “List Volume” and press Enter.
3. Now decide the Volume name, dive letter (Affected Read only volume, identified earlier from Disk Management).
4. Select the affected volume by using “Select volume x” command, where x is the volume number
5. One the affected volume is selected, now to clear the “Read-only” attribute, run the command “attributes volume clear readonly”. 

                       

And with this you are done, now your disk/volume should be writable.

You can check the same by running “detail volume” or “Attributes volume” command.

Note: Here one may ask here why I didn’t verify the disk/volume read/write attribute earlier and the short answer is yes, I did check and interestingly readonly attribute was set to No but still I have to clear the readonly attribute to make it writable again 😉.

In Case if your folders inside the drive are still not writable then run following cmd to remove the Read-only attribute and to set the System attribute.

C:\attrib -r +s drive:\folder_name 

Hope this would be helpful to others.........That's it :)