# Errors in production: explanation
The errors observed in production are listed in the following: (twiki page with the job exit codes can be found [here](https://twiki.cern.ch/twiki/bin/view/CMSPublic/JobExitCodes))
**53**
* **Phase space integration or un-reweighting efficiency problems**
* **Missing text file for fragment**
**73**
* **Missing files at Premix stage**
**134**
* **G4 error**
**139 - segmentation violation**
* **Merging problems**
* **Missing gridpacks**
* **NanoAOD problem**
**8001**
* **nThread problem**
**8003**
* **Premix error**
**8021**
* **Merging problem**
* **Server not available**
**50664**
* **Timeout - due to incorrect tune**
**60450**
* **Merging error due to server problem**
**99303**
* **Stageout problem**
**99305**
* **pLHE problem with too many events for time given**
**99996**
* **Module problem at NanoAOD stage**
* **53 :**
**Powheg + JHUGen phase space integration or unreweighting efficiency problems (physics process related errors )**
**lhe file contains fewer events than were requested ⇒ phase space problem. (physics process related errors )**
**73 :**
**Pythia8 :**
**vanishing cross section (physics process related errors )**
**134:**
**Mg leading order patching problem, + nb of threads issue. (not physics process related errors**
**139 : mainly : file access , request configuration issues. (not physics process related errors )**
**8001:**
**Only 1 request with this exit code , error related to premixing step (not physics process related errors )**
**50115 :**
**Mad + pythia8 : (not a physics process related problem). Issue observed in premixing step.**
**Needs more investigation, for few other requests.**\