Hello,
We’ve been experiencing this write timed out on tags that are running on client timer scripts.
Any idea how we can get rid of this?
Thank you! 
That particular timeout indicates that the client is timing out waiting for a result. The clients will only wait 30 seconds for a result- the write may still complete successfully, but after 30 seconds the client will stop waiting for the result (this timeout should be made settable, but currently isn’t).
The first thing to do would be to try to figure out why a write is taking over 30 seconds. This isn’t necessarily easy, but often there are more writes occurring than expected. You can trace through the OPC server and/or Device statistics to try to see what is going on.
Very often, when people run into this problem, it’s because they’re issuing a series of writes one at a time. Using the functions that write to multiple tags at once can be much more efficient. However, we made writing to multiple tags at once much more efficient in 7.7.5, so if you’re already using the multi-tag functions, trying out 7.7.5-rc2 might be worthwhile (it should be out next week, I think)
Regards,