Please click on the below links to download Lightroom 4.4.1 update.
Once done, please install the updates.
Let me know if this helps.
The update worked, thank you. I still cannot use the HDR function, which I thought was available on this version.
Lightroom version 4 has been out of production for several years. The HDR feature you are looking for is only available with the latest versions of Lightroom, Lightroom CC creative cloud subscription or Lightroom 6 standalone version. Either of these are paid upgrades for you. The creative cloud subscription program which includes the latest Photoshop is $9.99/month US. The Lightroom 6 standalone upgrade is $79.99 US.