You have master templates that use the put_in_document function. Intermittently when such a master template is run, you receive the following runtime error:
FATAL ERROR IOL0211: Failed to copy OLE2 object pool (1-0003-0020)
The error code 1-0003-0020 indicates a share violation. A temporary file of KCCM is locked by an external process. This prevents KCCM from generating the document and the IOL0211 error is raised.
In most cases the culprit is a virus scanner installed on the same machine. To resolve your issue, exclude the whole CCM folder in your anti-virus software. If the issue still persists, you can use a program such as Process Monitor (a.k.a ProcMon) to determine what program locks the temporary files used by KCCM.