# SerialVersionUID mismatch after upgrade

**URL:** <https://forum.inductiveautomation.com/t/serialversionuid-mismatch-after-upgrade/88800>\
**Category:** Ignition\
**Tags:** ignition81, perspective\
**Created:** [April 15, 2024, 7:52am UTC](https://forum.inductiveautomation.com/t/serialversionuid-mismatch-after-upgrade/88800 "2024-04-15T07:52:46Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![Rickard\_Nordwall](https://avatars.discourse-cdn.com/v4/letter/r/46a35a/32.png) [@Rickard\_Nordwall](https://forum.inductiveautomation.com/u/Rickard_Nordwall)\
**Post date:** [April 15, 2024, 7:52am UTC](https://forum.inductiveautomation.com/t/serialversionuid-mismatch-after-upgrade/88800/1 "2024-04-15T07:52:46Z")

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Hi,  
I upgraded Ignition 8.1.18 to 8.1.38 (perspective).  
In one view I have a dashboard with widgets on. I let operators add and remove widgets as they like. When I do changes I take the widgets and do a serialize of the data and stores it to a database. To view the data I do a query on the database and deserialize it. But after the update the builtin 'SerialVersionUID' changed and won't let me deserialize the data. Is there a way to change the 'SerialVersionUID' from a script?  
Otherwise could you help me fix this?

Best regards,  
Rickard Nordwall

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**Author:** ![pturmel](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/pturmel/32/3295_2.png) [@pturmel](https://forum.inductiveautomation.com/u/pturmel)\
**Post date:** [April 15, 2024, 12:02pm UTC](https://forum.inductiveautomation.com/t/serialversionuid-mismatch-after-upgrade/88800/2 "2024-04-15T12:02:33Z")

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Nope, you're out of luck. (What possessed you to use java serialization for this purpose instead of JSON?)

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<div class="post-metadata">

**Author:** ![pturmel](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/pturmel/32/3295_2.png) [@pturmel](https://forum.inductiveautomation.com/u/pturmel)\
**Post date:** [April 15, 2024, 12:05pm UTC](https://forum.inductiveautomation.com/t/serialversionuid-mismatch-after-upgrade/88800/3 "2024-04-15T12:05:14Z")

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Consider setting up an empty v8.1.18 gateway in trial mode with a database connection, just so you can run a script that deserializes all of those records, and re-encodes them as JSON (to a new column, presumably).

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<div class="post-metadata">

**Author:** ![Rickard\_Nordwall](https://avatars.discourse-cdn.com/v4/letter/r/46a35a/32.png) [@Rickard\_Nordwall](https://forum.inductiveautomation.com/u/Rickard_Nordwall)\
**Post date:** [April 15, 2024, 12:35pm UTC](https://forum.inductiveautomation.com/t/serialversionuid-mismatch-after-upgrade/88800/4 "2024-04-15T12:35:25Z")

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Thanks for the reply! Sad news but I will try setup a 8.1.18 again and do as you said. The reason for using serialize is unknown it was done before I joined the project, but I guess, if it works it works, was sort of the thought behind it.