[א' דר"ח כסלו, ה'תשל"ב]
שלום וברכה!
באם
החנויות שפותח עתה בשותפות (וגם הקודמות שהוא שותף בהן) סגורות בשויו"ט (כולל, כמובן, ליל שויו"ט) – יה"ר שתהא פתיחתן בהצלחה וכו'.
באם לאו,
ח"ו
: יַמשיך בה
j"b
שלו עתה.
אזכיר עה"צ.
On the first day of Rosh Chodesh Kislev, 5732.
Shalom u'Vrachah!
If the stores you are now opening in partnership (and also the previous ones in which you are a partner) are closed on Shabbos (including, of course, Friday night), then may their opening be with success, etc.
If not, you should continue with your current job for now. I will mention it at the Tziyun.
Summary
The Rebbe teaches that business ventures must fully observe Shabbos to merit blessing and success. If this condition is not met, one should refrain from entering such partnerships and continue with their current occupation.