Tested on Chrome and Firefox on Win 10, Chrome on Mac.

I lost the ability to create new Order Lines a week or so back. The button is simply not there. Please see attached screen capture. I'm getting a script error quite often when opening any Project Contract records. In case this is related... No customizations to the order entity have been made.

MsP2C.CrmSolution.DisableMaintainedExternallyForm@https://psa-preview.crm4.dynamics.com/%7b636647711550000197%7d/webresources/msdynce_p2c.js:43:1

j</e.prototype.executeFunction@https://psa-preview.crm4.dynamics.com/uclient/scripts/app.js?v=1.3.75-180427-041927:640:54151

j</e.prototype.execute@https://psa-preview.crm4.dynamics.com/uclient/scripts/app.js?v=1.3.75-180427-041927:640:53956

A</e.prototype._executeIndividualEvent@https://psa-preview.crm4.dynamics.com/uclient/scripts/app.js?v=1.3.75-180427-041927:640:46043

A</e.prototype._executeEventHandler@https://psa-preview.crm4.dynamics.com/uclient/scripts/app.js?v=1.3.75-180427-041927:640:44904

execute@https://psa-preview.crm4.dynamics.com/uclient/scripts/app.js?v=1.3.75-180427-041927:640:42738

_i</e.prototype._executeSyncAction@https://psa-preview.crm4.dynamics.com/uclient/scripts/app.js?v=1.3.75-180427-041927:775:48574

_i</e.prototype._executeSync@https://psa-preview.crm4.dynamics.com/uclient/scripts/app.js?v=1.3.75-180427-041927:775:48167

_i</e.prototype.executeAction@https://psa-preview.crm4.dynamics.com/uclient/scripts/app.js?v=1.3.75-180427-041927:775:47985

r@https://psa-preview.crm4.dynamics.com/uclient/scripts/app.js?v=1.3.75-180427-041927:736:603

$/<@https://psa-preview.crm4.dynamics.com/uclient/scripts/app.js?v=1.3.75-180427-041927:742:52

n@https://psa-preview.crm4.dynamics.com/uclient/scripts/app.js?v=1.3.75-180427-041927:736:247

dispatch@https://psa-preview.crm4.dynamics.com/uclient/scripts/app.js?v=1.3.75-180427-041927:736:152

m@https://psa-preview.crm4.dynamics.com/uclient/scripts/0.js?v=1.3.75-180427-041927:7:10183

execute/</</</</o</</<@https://psa-preview.crm4.dynamics.com/uclient/scripts/6.js?v=1.3.75-180427-041927:112:11903

r@https://psa-preview.crm4.dynamics.com/uclient/scripts/preload.js?v=1.3.75-180427-041927:23:62245

[442]/</</<[23]</e.exports/e.prototype._settlePromiseFromHandler@https://psa-preview.crm4.dynamics.com/uclient/scripts/preload.js?v=1.3.75-180427-041927:23:35907

[442]/</</<[23]</e.exports/e.prototype._settlePromiseAt@https://psa-preview.crm4.dynamics.com/uclient/scripts/preload.js?v=1.3.75-180427-041927:23:37234

[442]/</</<[23]</e.exports/e.prototype._settlePromiseAtPostResolution@https://psa-preview.crm4.dynamics.com/uclient/scripts/preload.js?v=1.3.75-180427-041927:23:31874

[442]/</</<[2]</n.prototype._drainQueue@https://psa-preview.crm4.dynamics.com/uclient/scripts/preload.js?v=1.3.75-180427-041927:23:2114

[442]/</</<[2]</n.prototype._drainQueues@https://psa-preview.crm4.dynamics.com/uclient/scripts/preload.js?v=1.3.75-180427-041927:23:2189

n/this.drainQueues@https://psa-preview.crm4.dynamics.com/uclient/scripts/preload.js?v=1.3.75-180427-041927:23:889