Employee attitude problem - politely worded letter about his misconduct?

Hello seniors, I am a HR executive from one of the non-profit organisations and wish to say that one of the lower member of staff is showing a kind of attitude to the staff. He is just 20 years and may be he isn\'t mature enough to deal with seniors and doesn't follow org\'s rules and regulations. Now his probation period just completed in August 01\'13 however, I am thinking to put him in observation period of two months.

Having said that I need a support from HR professionals that how would I write in a polite manner about his misconduct in a letter. should I directly mention about attitude problem..Can anybody suggest me of a politely worded but letter should be in such a way that he would take this as a warning letter at the same time realises his mistake too. I would require your assistance on this..Thanks..Simone

Hi Simone,
As his probation period is over, you should call him in for an appraisal.
At the appraisal you should inform him of his successes and failures.
Agree a Plan for Improvements, highlighting all the issues and setting a time frame (two months); at the end of which another appraisal will be conducted to discuss the improvements.
Confirm your Plan in writing but make it very clear, that if substantial improvements are not met then employment will be terminated.
Hope the above helps.
Regards,
Harsh

Hi,
if you have not confirmed his employment as yet. my recommendation would be to put him on action action plan for a review period of 30 days and in case his workplace conduct does not improve, you can go ahead and terminate him.
however in case you have already confirmed him, then you would need to put him on an action plan and initiate the Showcause route.
regards,

I echo Mr. Harsh, take appraisal and discuss the weaknesses of the said employee in detail i.e. his attitude towards his seniors not adhering the rules and regulations etc. which can be termed as misconduct and tell that his probation is extended for another 3 months, and will be observed for this extended probation and if no changes are seen, he will be terminated without further notice.