While attempting to apply the latest Oracle Critical Patch Update (CPU) to your Oracle DLP database, you encounter the following error:

...

Verifying environment and performing prerequisite checks...
Prerequisite check "CheckSystemSpace" failed.
The details are:
Required amount of space(1533453362) is not available.
[ Error during Prerequisite for apply Phase]. Detail: ApplySession failed during prerequisite checks
: Prerequisite check "CheckSystemSpace" failed.
Log file location: c:\app\<User Name>\product\11.2.0\dbhome_1\cfgtoollogs\opatch\opatch2011-12-30_
11-27-17AM.log

Recommended actions: Please look at log file to locate the prerequisite that failed. Invoke 'opatch
apply  -report' or 'opatch rollback  -report'.

OPatch failed with error code = 30

...

This is a space issue.

This error indicates that there is not enough space on the disk that contains the Oracle Home that is being patched.  Ensure that there is more than enough space on this disk by deleting unnecessary logs and files.  Try to have at least 2.5 Gigabytes of free space to allow for patching.