Try this, assuming that your eVar expires after visit:
Create a segment that:
Includes all hits where eVarX exists
Excludes all hits where eVarX does not exist
Open workspace any apply the segment to a panel
Drag over the hit depth dimension
This would give you general data on how many page views a user saw after hitting an error. If you wanted to see a specific error, you could change the segment to say 'eVarX equals error' instead of 'eVarX exists'.