It has been happening quite often that spam accounts are created and spam topics are posted. While nopCommerce team does its best to remove them asap, there are times when they are not around and the posts remain there till the time it's removed.
I think some members of the forum (may be MVPs or somebody you trust) should be made forum moderators. They can at the very least have capability to hide posts till it's approved/deleted by nopCommerce member.
Let me know if you need any help from my side. The real posts are hiding somewhere behind the bunch of spam posts. It really irritates to see those spammy posts covering half of active discussions.
Spam topics posted here in the nopCommerce forums are really getting out of control.
I thought there was a more recent topic about it, where I even posted a SQL trigger workaround that I use for preventing spam in the Contact Us page of my nop sites, but a Google search for my SQL does not find it? Was that topic removed? That simple workaround can prevent a lot of spam. (You can also include a search for exact same topic title posted in short period of time.)