One of the powerful features of AutoCAD is the ability for applications to built on top of it. Unfortunately, these applications can often leave remnants of themselves inside your drawings and cause performance issues. One such side effect is the buildup of Registered Applications or RegApps for short. These RegApps are left in the drawing’s Symbol table after entities that contained the XDATA (Extended Entity Data) they used are deleted.
While this can affect any user, this can be very common in the AEC industry as collaboration with external parties and trade partners means you’re typically referencing a lot of files from many sources. I’ve seen cases where a drawing with 50,000 RegApps can take 10 minutes to load and after clearing RegApps, takes merely seconds.
What most people don’t realize is that even though “RegApp” is an option with the PURGE command, using PURGE ALL will NOT remove them. You need to call PURGE separately, with only the REGAPP option. Click the following ScreenCast recording link to see a demonstration of this…
The video shows PURGE ALL and doesn’t list that any RegApps were removed. Purge is then called again, and only the REGAPP option is used which then removes several RegApps. Try it yourself, the drawing used was in the Sample Civil Sheet Set drawings that shipped with AutoCAD 2018.
Problem Keeps Returning?
External References (XREFS) and/or blocks can make the problem difficult to eliminate. You may need to process all Xrefs and block libraries to verify these RegApps aren’t being introduced from those sources. If you’ve used WBLOCK to save a block to disk from a RegApp corrupt drawing, that DWG file also has the issue.
Luckily, Autodesk has a batch utility (free) that will process multiple file/folders, automatically look in sub-folders as well as automatically load any referenced drawings as well.
Click the following ScreenCast link to see the process in action…
Depending on your version of AutoCAD, you can get this utility from the following links..
Schedule Cleanup After Hours
One last benefit if this utility is that it can be called from a DOS window with command like syntax. In a collaborative environment where Xrefs are being updated frequently by others, RegApps can keep getting reintroduced requiring this process to be run frequently. Because you can call this process completely automated from the a DOS prompt, this means you can create a batch file that’s scheduled to be run on a regular basis, even nightly on your drawing library. The following Screen Cast link shows how to call the utility from a DOS command prompt…