APAR - Stands for Authorized Program Anaylsis Report. It is an IBM report of a defect in the originally released program code of one of thier products. It may include notification of a PTF (Program Temporary Fix) to provide a solution or work around until the next full release of that programs is made which will include any fixes up to that point. The APAR generally tries to indicate when a permanent resolution will be provided. A customer will start the sequence of events that lead to an APAR by filing a SR/PMR (Service Request - Problem Management Record) when an issue is discovered. With the release MVS 3.8J which is legally available for the public to run most of the APARs have been addressed by either PTF or a community provided patch (quite a few original PTFs are no longer available) if you are using one of the pre-generated DASD images such as TK3-Upd or TK4 these PTFs have been addressed. And these have not. Jay Moseley's SYSGEN instructions uses a tape named ptfs.het to address all known issues with a resolution. His tutorial starts here.