about 4 years ago - Avanya - Direct link
I noticed one old mod, that you will want to unsubscribe and get a newer version of:
- Advanced Toolbar - I recommend More Advanced Toolbar or Resize It instead

I also recommend you try and get rid of the need for [ Backward Compatibility ] New Roads For Network Extension 2. The mod is not maintained consistantly, and if it breaks at some point and doesn't get updated, your city will not be able to load. It's better to use roads from the Roads category instead of this mod. Network Extensions 2 also offer some of these roads.

As for the error, let's try and clear all citizens and vehicles. That should reset all paths and hopefully solve it. To do that go into Options before loading your city. Then find the Loading Screen Mod on the left, and under options for it find the Safe Mode options. Enable both options to clear citizens and vehicles. Then load your city.

If that does the trick, make sure to turn those options off again. If not, upload the log again from that attempt to see if anything has helped at all.