# S7300Driver Exception Uncaught Trowable during messageArrive

**URL:** <https://forum.inductiveautomation.com/t/s7300driver-exception-uncaught-trowable-during-messagearrive/10766>\
**Category:** Ignition\
**Created:** [November 10, 2015, 1:08pm UTC](https://forum.inductiveautomation.com/t/s7300driver-exception-uncaught-trowable-during-messagearrive/10766 "2015-11-10T13:08:13Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![andrea.montresor](https://avatars.discourse-cdn.com/v4/letter/a/5f9b8f/32.png) [@andrea.montresor](https://forum.inductiveautomation.com/u/andrea.montresor)\
**Post date:** [November 10, 2015, 1:08pm UTC](https://forum.inductiveautomation.com/t/s7300driver-exception-uncaught-trowable-during-messagearrive/10766/1 "2015-11-10T13:08:13Z")

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Hello,

I’m trying to read data from a DataBlock on a Siemens S7 PLC.  
I’m able to read the datablock, but at certain point the following exception occurs.

From now on the “Quality” of each tag of the datablock passes to “BAD QUALITY” and I’m not able to read values anymore.  
Can someone help me with this issue?  
Thank you.

Andrea

 ![](https://us1.discourse-cdn.com/inductiveautomation/original/2X/6/65f0e948eeb93e1b2110743d007b99f375ac2f64.png)

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**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:** [November 10, 2015, 2:09pm UTC](https://forum.inductiveautomation.com/t/s7300driver-exception-uncaught-trowable-during-messagearrive/10766/2 "2015-11-10T14:09:50Z")

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Hmm, it seems there’s something wrong with the String you’re trying to read from the datablock.

How have you defined the address / item path for that String?