# RSLogix OPC server tags can not be read/write in desginer **URL:** \ **Category:** Ignition\ **Tags:** perspective, ignition81\ **Created:** [April 27, 2023, 12:29pm UTC](https://forum.inductiveautomation.com/t/rslogix-opc-server-tags-can-not-be-read-write-in-desginer/72958 "2023-04-27T12:29:20Z")\ **Posts on this page:** 6\ **Page:** 1
**Author:** ![ANKIT\_BARAD](https://avatars.discourse-cdn.com/v4/letter/a/6f9a4e/32.png) [@ANKIT\_BARAD](https://forum.inductiveautomation.com/u/ANKIT_BARAD)\ **Post date:** [April 27, 2023, 12:29pm UTC](https://forum.inductiveautomation.com/t/rslogix-opc-server-tags-can-not-be-read-write-in-desginer/72958/1 "2023-04-27T12:29:20Z")
I have connection between studio5000 emulator and Ignition via RSLinx OPC Server. I can read and write tags in gateway. However, I am unable to read or write tags in designer. ![Designer](https://us1.discourse-cdn.com/inductiveautomation/original/3X/8/9/898c576a1e1c6cbf9f83316fc59727030b14e776.png) ![Tags Reading in gateway](https://us1.discourse-cdn.com/inductiveautomation/original/3X/a/f/af7421f629be38b90636ea9ab460d36b0bdb5c17.png) ---
**Author:** ![Kevin.Herron](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/kevin.herron/32/7259_2.png) [@Kevin.Herron](https://forum.inductiveautomation.com/u/Kevin.Herron)\ **Post date:** [April 27, 2023, 12:51pm UTC](https://forum.inductiveautomation.com/t/rslogix-opc-server-tags-can-not-be-read-write-in-desginer/72958/2 "2023-04-27T12:51:10Z")
Does Subscribe work in the quick client instead of Read? ---
**Author:** ![ANKIT\_BARAD](https://avatars.discourse-cdn.com/v4/letter/a/6f9a4e/32.png) [@ANKIT\_BARAD](https://forum.inductiveautomation.com/u/ANKIT_BARAD)\ **Post date:** [April 27, 2023, 1:05pm UTC](https://forum.inductiveautomation.com/t/rslogix-opc-server-tags-can-not-be-read-write-in-desginer/72958/3 "2023-04-27T13:05:08Z")
No it shows uncertain\_initial value ![image](https://us1.discourse-cdn.com/inductiveautomation/original/3X/1/4/14c0f197775f1b71758d33c90a52b65d49a4c655.png) ---
**Author:** ![Kevin.Herron](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/kevin.herron/32/7259_2.png) [@Kevin.Herron](https://forum.inductiveautomation.com/u/Kevin.Herron)\ **Post date:** [April 27, 2023, 1:11pm UTC](https://forum.inductiveautomation.com/t/rslogix-opc-server-tags-can-not-be-read-write-in-desginer/72958/4 "2023-04-27T13:11:35Z")
If this is an OPC UA connection, set the log level for the loggers you get searching "OpcUaSubscriptionManager" and "OpcUaSubscriptionSynchronizer" to TRACE and then edit/save that connection. There should be some logs once the subscriptions are attempted that explain what's failing. [https://docs.inductiveautomation.com/display/DOC81/Diagnostics+-+Logs#DiagnosticsLogs-ChangingLoggingLevels](https://docs.inductiveautomation.com/display/DOC81/Diagnostics+-+Logs#DiagnosticsLogs-ChangingLoggingLevels) ---
**Author:** ![ANKIT\_BARAD](https://avatars.discourse-cdn.com/v4/letter/a/6f9a4e/32.png) [@ANKIT\_BARAD](https://forum.inductiveautomation.com/u/ANKIT_BARAD)\ **Post date:** [April 27, 2023, 2:06pm UTC](https://forum.inductiveautomation.com/t/rslogix-opc-server-tags-can-not-be-read-write-in-desginer/72958/5 "2023-04-27T14:06:45Z")
I solved it by changing tag group OPC data mode from subscribe to polled ![image](https://us1.discourse-cdn.com/inductiveautomation/original/3X/7/5/751109f13ff35a174dc201794df3b0e31d2fda34.png) ---
**Author:** ![Ryan\_Allen](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/ryan_allen/32/47013_2.png) [@Ryan\_Allen](https://forum.inductiveautomation.com/u/Ryan_Allen)\ **Post date:** [May 1, 2023, 12:19am UTC](https://forum.inductiveautomation.com/t/rslogix-opc-server-tags-can-not-be-read-write-in-desginer/72958/6 "2023-05-01T00:19:55Z")
So glad you asked this question, the unknown\_last known value was driving me crazy. Thanks for the solution