App Store hangs on Checking for Updates - 10.10.3

Had the same problem, and this is what solved it for me:

Open Activity Monitor.

Find the process namned "softwareupdated", which is probably using a lot of process power and memory. Force quit this process.

Done - the system should now tell you that it is about to restart in 1 minute.

Problem solved!
Thx a lot 🙂

Tried Jonas' suggestion but I can't find the softwareupdated process. Did a search again and found CNet's solution worked for me: http://www.cnet.com/news/tackle-a-hung-app-store-update-in-os-x/

Tried force quitting "softwareupdated" and the methods on the cnet link but still not fixed for me 😟

Any other suggestions? I tried to manually update it by downloading it from the Apple website. Went through the full process and restarted my Macbook, still says I'm running 10.10.3.

This article from OSXDaily.com tells you how to manually install the update in Terminal and it worked for me. Might be worth giving it a try.

http://osxdaily.com/2015/07/01/fix-frozen-app-store-updates-and-high-softwareupd ated-cpu/?utm_source=feedburner&utm_medi…

Once I input the command to update iTunes in terminal, the update for 10.10.4 also showed up and downloaded fine in the App Store. Thanks for the tip and OSXDaily.com