ERROR: Internal : Execution Timeout Expired.

[JoseGarduño]

Hello, I am trying to run a query looking for the completed items in the QW, but I get this error.

Currently there are 4644 elements in the Work Queue, previously when there were less elements in the work queue this error did not occur.

[Denis__Dennehy]

This is a query timeout error and seeing as you are using a tag filter I suspect it may be related to how you are using tags in your solution.
It might be worth revisiting tags in the Blue Prism University training to ensure what you are doing adheres to it. 
Firstly make sure that your tags are not unique identifiers,  the tag functionality should only be used for grouping logic.  So for example,  do not use a telephone number in a tag but do use Phone Model.

Secondly,  do not use any kind of wild card in your query or Tag Filter - I have seen this causing this exact same error before.  You will have to change the logic of your solution to no longer use them.  I just found another old thread in this forum saying it is fine to use wildcards in tag filters but I have definitely seen instances before with larger datasets where it causes timeouts.