The Malaysian government has long recognized the significance of mastering the English language among its citizenry. The government has planned, and subsequently, implemented many policies to ensure Malaysians master the English language. Although civil servants have a strong desire to master the English language to perform their duties more efficiently, poor English communication skills have become a major concern in this regard. Therefore, this research aims to investigate common errors in writing the English language among non-academic staff at "Universiti Sultan Zainal Abidin" (UniSZA), a public university in Malaysia. The study employed an Error Analysis approach by conducting document analysis where every respondent was required to write a paragraph in the English language in about 150-200 words on the topic "My greatest challenge as a UniSZA officer". The findings revealed that a sizeable number of non-academic staff committed different types of errors in writing the English language, including errors related to subject-verb agreement, passive voice, plurality, choice of word, omission of word, use of article, tense sequence, word ordering, gerund, addition of word/redundancy, and comparison of adjective. It was observed that lack of linguistic skills, lack of exposure, and inadequate practices in written English were the main factors contributing to the English writing errors among the non-academic staff. These findings could help the university management to develop appropriate programs that can assist the non-academic staff to develop English writing competence. However, this study is limited to English writing errors. Further research may focus on other language skills such as speaking and listening.