Sparks locks my computer

I am currently on Spark v 2.6.3

Every time someone sends me a new message, it locks up everything I am working in (i.e. Email, Excel, Word) until I click on the message to see what it says. How do I stop this from happening?

By lock up you probably mean that new Spark message steals your cursor from other program you are working with? Anyway, you can install this version (latest build) and it should have this fixed ll4j/spark_2_7_0_668.exe