Ignition 7.5 and Kepserver 4.5

Currently running FSQL and FPMI, looking to possibly upgrade to ignition, so using a laptop have been working with ignition 7.5 and Kepserver 4.5 but having small issue that i am certain is some check mark in some box some place just not sure where.

I followed the videos and such and I have successfully linked to my Kepserver. Had to take the check marks out of the async and the keep alive in order for the connection to remain stable, if i didnt it would go offline then online and keep going up and down. Both the Kepserver and ignition are on the same PC along with MySql.

Using Kepserver I can OPC quick client and i can see all my tags and groups and the data associated with each.

In the ignition software I can see kepserver, i can see all my tags and groups, and when i look at the tags there are 3 options, subscription, read, and write. If I read or write to the tags everything is good, no problems.

If I subscribe to the tags, i get stale bad data. I have been looking over all the various check boxes and have tried unchecking each one then testing and if that didnt work rechecked it. As I said the only way i can get it to at least read and write the tags is by having the keep alive and async off.

Looking for any ideas on what i am missing as to why i can read and write but cant subscribe.

Thanks and have a great day

The ability to read but not subscribe is a classic sign of DCOM problems, which can occur even on local machines. Kepware 4.5 can run as a service, but usually is configured to run as an application- and with Ignition running under “system”, it’s probably being blocked.

A few options (pick one):
a) Run kepware as a service. This will put it under the system account by default, which should solve the problem.
b) Change Ignition to run as the same user as the logged in account, instead of “system”. You do this by going to Control Panel>Administrative Tools>Services, and then then right click Ignition and select “properties”.
c) Upgrade Kepware to 5+, which always runs as a service. Then, though the COM connection should now work, you could also connect over OPC-UA, which won’t have this problem.

Some versions of kepware had a problem with the keepalive option, so leave that off. The async problem is a different manifestation of this subscription problem, so once subscriptions work, async ops should also work.