@gksteele6205 

Don't take the advice given by @GianSeth_A.  It's very wrong.  It's unbelievable how QB employees don't even know how their system works.

The proper way to handle stale checks is to create deposits dated in the current period to offset the stale checks.  Then, clear the deposits against the stale checks next time you reconcile. 

@GianSeth_A 

Your advice is terribly inaccurate and misleading and will cause changes to closed periods.  You never void a check from a closed period in QBO because QBO does not make "the necessary adjustments when you void checks."  All QBO does when voiding a check is zero the original entry made when the check was issued.  BTW, your journal entries are creating more checks, not reversing the stale ones.