Mar 18 2015

Windows reports incorrect free space on a disk

I had an interesting one today. Received a call for a disk that is running out of disk space and I thought, easy, quickly log on and clear some space.

It turns out that the total data on the disk was 5GB in size, with the disk being 40GB in capacity, but the available free space reported was 4GB. This baffled me a bit but after some assistance from an internet search and colleague we quickly found that the problem was related to shadow copies taking up space.

In our scenario, shadow copies were disabled but running vssadmin list shadowstorage in the cmd line told us a different story. The output showed that shadow copies was indeed taking up most of the disk space.

To resolve this we enable and disabled shadow copies for the disk. Set the limit for shadow copies to a small amount of disk space and then enabled shadow copies again.

Voila! We got back our used disk space.


Jan 8 2015

Outlook Web Access stops working after renewing 3rd party Certificate

We had an interesting issue this week. We renewed our Exchange certificate with a 3rd party vendor. Installed the certificate on Exchange and ISA Server.

OWA access from the internet stopped working after we installed the certificates. We tested OWA internally and it worked which pointed to something on the ISA server. After a long investigation we found the issue to be ISA running on Windows 2003 which is not compatible with the Secure Hash Algorithm 2 (SHA2) family of hashing algorithms that the certificates from our 3rd party cert provider issues.

Microsoft has a hotfix available to get around this. We were able to access OWA from the internet after installing this hotfix on the ISA server running Windows 2003 Server.

The Microsoft article can be found below. You will find more technical detail within this article and have the opportunity to download the hotfix. Note that you need to restart your Windows 2003 Server after installing the hotfix.

Microsoft KB938397