Unable to change value of memory tag

I just created a memory tag in the designer, string type. When I try to change the value of the tag in the designer, I get the message: “Error writing to .Value: Null”. The designer is in r/w mode and the tag itself has r/w permission. I’ve tried relaunching the designer. Using Ignition 7.6.4. The tag is used only in a client start-up script. Any ideas?

Using 7.6.6 here and I’m able to either manually change the value of a string type memory tag in the designer, or by using scripting on a button’s property change event as below for a string type memory tag named MyStringTag.

system.tag.write(“MyStringTag”, “My new string value”)

I don’t remember 7.6.4 having any problems with memory tags. You might try creating another memory tag to test with. It should work.

What is the script you are using to write to the tag?

The scripts are only reading the tag and I have no issues there. I’m trying to change the string in the designer, either in the SQL tag tree view or the tag properties itself. The tag will be pretty much used as a constant, but I need to be able to change the value while I’m developing the scripts. I checked the system console and no messages show up when I get the error in the designer.

I have been trying to troubleshoot this without success. I have tried writing directly to the tag in a tag.write script, and also by writing to the tag in the SQLTag browser. Both methods did not reproduce the issue in Ignition 7.6.6.

Have you tried restarting the SQLTag Realtime provider? All you need to do is edit and save
Have you restarted your gateway?